1 /*
2 * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // Must be at least Windows Vista or Server 2008 to use InitOnceExecuteOnce
26 #define _WIN32_WINNT 0x0600
27
28 // no precompiled headers
29 #include "jvm.h"
30 #include "classfile/classLoader.hpp"
31 #include "classfile/systemDictionary.hpp"
32 #include "classfile/vmSymbols.hpp"
33 #include "code/icBuffer.hpp"
34 #include "code/vtableStubs.hpp"
35 #include "compiler/compileBroker.hpp"
36 #include "compiler/disassembler.hpp"
37 #include "interpreter/interpreter.hpp"
38 #include "logging/log.hpp"
39 #include "memory/allocation.inline.hpp"
40 #include "memory/filemap.hpp"
41 #include "oops/oop.inline.hpp"
42 #include "os_share_windows.hpp"
43 #include "os_windows.inline.hpp"
44 #include "prims/jniFastGetField.hpp"
45 #include "prims/jvm_misc.hpp"
46 #include "runtime/arguments.hpp"
47 #include "runtime/atomic.hpp"
48 #include "runtime/extendedPC.hpp"
49 #include "runtime/globals.hpp"
50 #include "runtime/interfaceSupport.hpp"
51 #include "runtime/java.hpp"
52 #include "runtime/javaCalls.hpp"
53 #include "runtime/mutexLocker.hpp"
54 #include "runtime/objectMonitor.hpp"
55 #include "runtime/orderAccess.inline.hpp"
56 #include "runtime/osThread.hpp"
57 #include "runtime/perfMemory.hpp"
58 #include "runtime/sharedRuntime.hpp"
59 #include "runtime/statSampler.hpp"
60 #include "runtime/stubRoutines.hpp"
61 #include "runtime/thread.inline.hpp"
62 #include "runtime/threadCritical.hpp"
63 #include "runtime/timer.hpp"
64 #include "runtime/vm_version.hpp"
65 #include "semaphore_windows.hpp"
66 #include "services/attachListener.hpp"
67 #include "services/memTracker.hpp"
68 #include "services/runtimeService.hpp"
69 #include "utilities/align.hpp"
70 #include "utilities/decoder.hpp"
71 #include "utilities/defaultStream.hpp"
72 #include "utilities/events.hpp"
73 #include "utilities/growableArray.hpp"
74 #include "utilities/macros.hpp"
75 #include "utilities/vmError.hpp"
76 #include "symbolengine.hpp"
77 #include "windbghelp.hpp"
78
79
80 #ifdef _DEBUG
81 #include <crtdbg.h>
82 #endif
83
84
85 #include <windows.h>
86 #include <sys/types.h>
87 #include <sys/stat.h>
88 #include <sys/timeb.h>
89 #include <objidl.h>
90 #include <shlobj.h>
91
92 #include <malloc.h>
93 #include <signal.h>
94 #include <direct.h>
95 #include <errno.h>
96 #include <fcntl.h>
97 #include <io.h>
98 #include <process.h> // For _beginthreadex(), _endthreadex()
99 #include <imagehlp.h> // For os::dll_address_to_function_name
100 // for enumerating dll libraries
101 #include <vdmdbg.h>
102 #include <psapi.h>
103
104 // for timer info max values which include all bits
105 #define ALL_64_BITS CONST64(-1)
106
107 // For DLL loading/load error detection
108 // Values of PE COFF
109 #define IMAGE_FILE_PTR_TO_SIGNATURE 0x3c
110 #define IMAGE_FILE_SIGNATURE_LENGTH 4
111
112 static HANDLE main_process;
113 static HANDLE main_thread;
114 static int main_thread_id;
115
116 static FILETIME process_creation_time;
117 static FILETIME process_exit_time;
118 static FILETIME process_user_time;
119 static FILETIME process_kernel_time;
120
121 #ifdef _M_AMD64
122 #define __CPU__ amd64
123 #else
124 #define __CPU__ i486
125 #endif
126
127 // save DLL module handle, used by GetModuleFileName
128
129 HINSTANCE vm_lib_handle;
130
131 BOOL WINAPI DllMain(HINSTANCE hinst, DWORD reason, LPVOID reserved) {
132 switch (reason) {
133 case DLL_PROCESS_ATTACH:
134 vm_lib_handle = hinst;
135 if (ForceTimeHighResolution) {
136 timeBeginPeriod(1L);
137 }
138 WindowsDbgHelp::pre_initialize();
139 SymbolEngine::pre_initialize();
140 break;
141 case DLL_PROCESS_DETACH:
142 if (ForceTimeHighResolution) {
143 timeEndPeriod(1L);
144 }
145 break;
146 default:
147 break;
148 }
149 return true;
150 }
151
152 static inline double fileTimeAsDouble(FILETIME* time) {
153 const double high = (double) ((unsigned int) ~0);
154 const double split = 10000000.0;
155 double result = (time->dwLowDateTime / split) +
156 time->dwHighDateTime * (high/split);
157 return result;
158 }
159
160 // Implementation of os
161
162 bool os::unsetenv(const char* name) {
163 assert(name != NULL, "Null pointer");
164 return (SetEnvironmentVariable(name, NULL) == TRUE);
165 }
166
167 // No setuid programs under Windows.
168 bool os::have_special_privileges() {
169 return false;
170 }
171
172
173 // This method is a periodic task to check for misbehaving JNI applications
174 // under CheckJNI, we can add any periodic checks here.
175 // For Windows at the moment does nothing
176 void os::run_periodic_checks() {
177 return;
178 }
179
180 // previous UnhandledExceptionFilter, if there is one
181 static LPTOP_LEVEL_EXCEPTION_FILTER prev_uef_handler = NULL;
182
183 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo);
184
185 void os::init_system_properties_values() {
186 // sysclasspath, java_home, dll_dir
187 {
188 char *home_path;
189 char *dll_path;
190 char *pslash;
191 char *bin = "\\bin";
192 char home_dir[MAX_PATH + 1];
193 char *alt_home_dir = ::getenv("_ALT_JAVA_HOME_DIR");
194
195 if (alt_home_dir != NULL) {
196 strncpy(home_dir, alt_home_dir, MAX_PATH + 1);
197 home_dir[MAX_PATH] = '\0';
198 } else {
199 os::jvm_path(home_dir, sizeof(home_dir));
200 // Found the full path to jvm.dll.
201 // Now cut the path to <java_home>/jre if we can.
202 *(strrchr(home_dir, '\\')) = '\0'; // get rid of \jvm.dll
203 pslash = strrchr(home_dir, '\\');
204 if (pslash != NULL) {
205 *pslash = '\0'; // get rid of \{client|server}
206 pslash = strrchr(home_dir, '\\');
207 if (pslash != NULL) {
208 *pslash = '\0'; // get rid of \bin
209 }
210 }
211 }
212
213 home_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + 1, mtInternal);
214 if (home_path == NULL) {
215 return;
216 }
217 strcpy(home_path, home_dir);
218 Arguments::set_java_home(home_path);
219 FREE_C_HEAP_ARRAY(char, home_path);
220
221 dll_path = NEW_C_HEAP_ARRAY(char, strlen(home_dir) + strlen(bin) + 1,
222 mtInternal);
223 if (dll_path == NULL) {
224 return;
225 }
226 strcpy(dll_path, home_dir);
227 strcat(dll_path, bin);
228 Arguments::set_dll_dir(dll_path);
229 FREE_C_HEAP_ARRAY(char, dll_path);
230
231 if (!set_boot_path('\\', ';')) {
232 return;
233 }
234 }
235
236 // library_path
237 #define EXT_DIR "\\lib\\ext"
238 #define BIN_DIR "\\bin"
239 #define PACKAGE_DIR "\\Sun\\Java"
240 {
241 // Win32 library search order (See the documentation for LoadLibrary):
242 //
243 // 1. The directory from which application is loaded.
244 // 2. The system wide Java Extensions directory (Java only)
245 // 3. System directory (GetSystemDirectory)
246 // 4. Windows directory (GetWindowsDirectory)
247 // 5. The PATH environment variable
248 // 6. The current directory
249
250 char *library_path;
251 char tmp[MAX_PATH];
252 char *path_str = ::getenv("PATH");
253
254 library_path = NEW_C_HEAP_ARRAY(char, MAX_PATH * 5 + sizeof(PACKAGE_DIR) +
255 sizeof(BIN_DIR) + (path_str ? strlen(path_str) : 0) + 10, mtInternal);
256
257 library_path[0] = '\0';
258
259 GetModuleFileName(NULL, tmp, sizeof(tmp));
260 *(strrchr(tmp, '\\')) = '\0';
261 strcat(library_path, tmp);
262
263 GetWindowsDirectory(tmp, sizeof(tmp));
264 strcat(library_path, ";");
265 strcat(library_path, tmp);
266 strcat(library_path, PACKAGE_DIR BIN_DIR);
267
268 GetSystemDirectory(tmp, sizeof(tmp));
269 strcat(library_path, ";");
270 strcat(library_path, tmp);
271
272 GetWindowsDirectory(tmp, sizeof(tmp));
273 strcat(library_path, ";");
274 strcat(library_path, tmp);
275
276 if (path_str) {
277 strcat(library_path, ";");
278 strcat(library_path, path_str);
279 }
280
281 strcat(library_path, ";.");
282
283 Arguments::set_library_path(library_path);
284 FREE_C_HEAP_ARRAY(char, library_path);
285 }
286
287 // Default extensions directory
288 {
289 char path[MAX_PATH];
290 char buf[2 * MAX_PATH + 2 * sizeof(EXT_DIR) + sizeof(PACKAGE_DIR) + 1];
291 GetWindowsDirectory(path, MAX_PATH);
292 sprintf(buf, "%s%s;%s%s%s", Arguments::get_java_home(), EXT_DIR,
293 path, PACKAGE_DIR, EXT_DIR);
294 Arguments::set_ext_dirs(buf);
295 }
296 #undef EXT_DIR
297 #undef BIN_DIR
298 #undef PACKAGE_DIR
299
300 #ifndef _WIN64
301 // set our UnhandledExceptionFilter and save any previous one
302 prev_uef_handler = SetUnhandledExceptionFilter(Handle_FLT_Exception);
303 #endif
304
305 // Done
306 return;
307 }
308
309 void os::breakpoint() {
310 DebugBreak();
311 }
312
313 // Invoked from the BREAKPOINT Macro
314 extern "C" void breakpoint() {
315 os::breakpoint();
316 }
317
318 // RtlCaptureStackBackTrace Windows API may not exist prior to Windows XP.
319 // So far, this method is only used by Native Memory Tracking, which is
320 // only supported on Windows XP or later.
321 //
322 int os::get_native_stack(address* stack, int frames, int toSkip) {
323 int captured = RtlCaptureStackBackTrace(toSkip + 1, frames, (PVOID*)stack, NULL);
324 for (int index = captured; index < frames; index ++) {
325 stack[index] = NULL;
326 }
327 return captured;
328 }
329
330
331 // os::current_stack_base()
332 //
333 // Returns the base of the stack, which is the stack's
334 // starting address. This function must be called
335 // while running on the stack of the thread being queried.
336
337 address os::current_stack_base() {
338 MEMORY_BASIC_INFORMATION minfo;
339 address stack_bottom;
340 size_t stack_size;
341
342 VirtualQuery(&minfo, &minfo, sizeof(minfo));
343 stack_bottom = (address)minfo.AllocationBase;
344 stack_size = minfo.RegionSize;
345
346 // Add up the sizes of all the regions with the same
347 // AllocationBase.
348 while (1) {
349 VirtualQuery(stack_bottom+stack_size, &minfo, sizeof(minfo));
350 if (stack_bottom == (address)minfo.AllocationBase) {
351 stack_size += minfo.RegionSize;
352 } else {
353 break;
354 }
355 }
356 return stack_bottom + stack_size;
357 }
358
359 size_t os::current_stack_size() {
360 size_t sz;
361 MEMORY_BASIC_INFORMATION minfo;
362 VirtualQuery(&minfo, &minfo, sizeof(minfo));
363 sz = (size_t)os::current_stack_base() - (size_t)minfo.AllocationBase;
364 return sz;
365 }
366
367 struct tm* os::localtime_pd(const time_t* clock, struct tm* res) {
368 const struct tm* time_struct_ptr = localtime(clock);
369 if (time_struct_ptr != NULL) {
370 *res = *time_struct_ptr;
371 return res;
372 }
373 return NULL;
374 }
375
376 struct tm* os::gmtime_pd(const time_t* clock, struct tm* res) {
377 const struct tm* time_struct_ptr = gmtime(clock);
378 if (time_struct_ptr != NULL) {
379 *res = *time_struct_ptr;
380 return res;
381 }
382 return NULL;
383 }
384
385 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo);
386
387 // Thread start routine for all newly created threads
388 static unsigned __stdcall thread_native_entry(Thread* thread) {
389 // Try to randomize the cache line index of hot stack frames.
390 // This helps when threads of the same stack traces evict each other's
391 // cache lines. The threads can be either from the same JVM instance, or
392 // from different JVM instances. The benefit is especially true for
393 // processors with hyperthreading technology.
394 static int counter = 0;
395 int pid = os::current_process_id();
396 _alloca(((pid ^ counter++) & 7) * 128);
397
398 thread->initialize_thread_current();
399
400 OSThread* osthr = thread->osthread();
401 assert(osthr->get_state() == RUNNABLE, "invalid os thread state");
402
403 if (UseNUMA) {
404 int lgrp_id = os::numa_get_group_id();
405 if (lgrp_id != -1) {
406 thread->set_lgrp_id(lgrp_id);
407 }
408 }
409
410 // Diagnostic code to investigate JDK-6573254
411 int res = 30115; // non-java thread
412 if (thread->is_Java_thread()) {
413 res = 20115; // java thread
414 }
415
416 log_info(os, thread)("Thread is alive (tid: " UINTX_FORMAT ").", os::current_thread_id());
417
418 // Install a win32 structured exception handler around every thread created
419 // by VM, so VM can generate error dump when an exception occurred in non-
420 // Java thread (e.g. VM thread).
421 __try {
422 thread->run();
423 } __except(topLevelExceptionFilter(
424 (_EXCEPTION_POINTERS*)_exception_info())) {
425 // Nothing to do.
426 }
427
428 log_info(os, thread)("Thread finished (tid: " UINTX_FORMAT ").", os::current_thread_id());
429
430 // One less thread is executing
431 // When the VMThread gets here, the main thread may have already exited
432 // which frees the CodeHeap containing the Atomic::add code
433 if (thread != VMThread::vm_thread() && VMThread::vm_thread() != NULL) {
434 Atomic::dec(&os::win32::_os_thread_count);
435 }
436
437 // If a thread has not deleted itself ("delete this") as part of its
438 // termination sequence, we have to ensure thread-local-storage is
439 // cleared before we actually terminate. No threads should ever be
440 // deleted asynchronously with respect to their termination.
441 if (Thread::current_or_null_safe() != NULL) {
442 assert(Thread::current_or_null_safe() == thread, "current thread is wrong");
443 thread->clear_thread_current();
444 }
445
446 // Thread must not return from exit_process_or_thread(), but if it does,
447 // let it proceed to exit normally
448 return (unsigned)os::win32::exit_process_or_thread(os::win32::EPT_THREAD, res);
449 }
450
451 static OSThread* create_os_thread(Thread* thread, HANDLE thread_handle,
452 int thread_id) {
453 // Allocate the OSThread object
454 OSThread* osthread = new OSThread(NULL, NULL);
455 if (osthread == NULL) return NULL;
456
457 // Initialize support for Java interrupts
458 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
459 if (interrupt_event == NULL) {
460 delete osthread;
461 return NULL;
462 }
463 osthread->set_interrupt_event(interrupt_event);
464
465 // Store info on the Win32 thread into the OSThread
466 osthread->set_thread_handle(thread_handle);
467 osthread->set_thread_id(thread_id);
468
469 if (UseNUMA) {
470 int lgrp_id = os::numa_get_group_id();
471 if (lgrp_id != -1) {
472 thread->set_lgrp_id(lgrp_id);
473 }
474 }
475
476 // Initial thread state is INITIALIZED, not SUSPENDED
477 osthread->set_state(INITIALIZED);
478
479 return osthread;
480 }
481
482
483 bool os::create_attached_thread(JavaThread* thread) {
484 #ifdef ASSERT
485 thread->verify_not_published();
486 #endif
487 HANDLE thread_h;
488 if (!DuplicateHandle(main_process, GetCurrentThread(), GetCurrentProcess(),
489 &thread_h, THREAD_ALL_ACCESS, false, 0)) {
490 fatal("DuplicateHandle failed\n");
491 }
492 OSThread* osthread = create_os_thread(thread, thread_h,
493 (int)current_thread_id());
494 if (osthread == NULL) {
495 return false;
496 }
497
498 // Initial thread state is RUNNABLE
499 osthread->set_state(RUNNABLE);
500
501 thread->set_osthread(osthread);
502
503 log_info(os, thread)("Thread attached (tid: " UINTX_FORMAT ").",
504 os::current_thread_id());
505
506 return true;
507 }
508
509 bool os::create_main_thread(JavaThread* thread) {
510 #ifdef ASSERT
511 thread->verify_not_published();
512 #endif
513 if (_starting_thread == NULL) {
514 _starting_thread = create_os_thread(thread, main_thread, main_thread_id);
515 if (_starting_thread == NULL) {
516 return false;
517 }
518 }
519
520 // The primordial thread is runnable from the start)
521 _starting_thread->set_state(RUNNABLE);
522
523 thread->set_osthread(_starting_thread);
524 return true;
525 }
526
527 // Helper function to trace _beginthreadex attributes,
528 // similar to os::Posix::describe_pthread_attr()
529 static char* describe_beginthreadex_attributes(char* buf, size_t buflen,
530 size_t stacksize, unsigned initflag) {
531 stringStream ss(buf, buflen);
532 if (stacksize == 0) {
533 ss.print("stacksize: default, ");
534 } else {
535 ss.print("stacksize: " SIZE_FORMAT "k, ", stacksize / 1024);
536 }
537 ss.print("flags: ");
538 #define PRINT_FLAG(f) if (initflag & f) ss.print( #f " ");
539 #define ALL(X) \
540 X(CREATE_SUSPENDED) \
541 X(STACK_SIZE_PARAM_IS_A_RESERVATION)
542 ALL(PRINT_FLAG)
543 #undef ALL
544 #undef PRINT_FLAG
545 return buf;
546 }
547
548 // Allocate and initialize a new OSThread
549 bool os::create_thread(Thread* thread, ThreadType thr_type,
550 size_t stack_size) {
551 unsigned thread_id;
552
553 // Allocate the OSThread object
554 OSThread* osthread = new OSThread(NULL, NULL);
555 if (osthread == NULL) {
556 return false;
557 }
558
559 // Initialize support for Java interrupts
560 HANDLE interrupt_event = CreateEvent(NULL, true, false, NULL);
561 if (interrupt_event == NULL) {
562 delete osthread;
563 return NULL;
564 }
565 osthread->set_interrupt_event(interrupt_event);
566 osthread->set_interrupted(false);
567
568 thread->set_osthread(osthread);
569
570 if (stack_size == 0) {
571 switch (thr_type) {
572 case os::java_thread:
573 // Java threads use ThreadStackSize which default value can be changed with the flag -Xss
574 if (JavaThread::stack_size_at_create() > 0) {
575 stack_size = JavaThread::stack_size_at_create();
576 }
577 break;
578 case os::compiler_thread:
579 if (CompilerThreadStackSize > 0) {
580 stack_size = (size_t)(CompilerThreadStackSize * K);
581 break;
582 } // else fall through:
583 // use VMThreadStackSize if CompilerThreadStackSize is not defined
584 case os::vm_thread:
585 case os::pgc_thread:
586 case os::cgc_thread:
587 case os::watcher_thread:
588 if (VMThreadStackSize > 0) stack_size = (size_t)(VMThreadStackSize * K);
589 break;
590 }
591 }
592
593 // Create the Win32 thread
594 //
595 // Contrary to what MSDN document says, "stack_size" in _beginthreadex()
596 // does not specify stack size. Instead, it specifies the size of
597 // initially committed space. The stack size is determined by
598 // PE header in the executable. If the committed "stack_size" is larger
599 // than default value in the PE header, the stack is rounded up to the
600 // nearest multiple of 1MB. For example if the launcher has default
601 // stack size of 320k, specifying any size less than 320k does not
602 // affect the actual stack size at all, it only affects the initial
603 // commitment. On the other hand, specifying 'stack_size' larger than
604 // default value may cause significant increase in memory usage, because
605 // not only the stack space will be rounded up to MB, but also the
606 // entire space is committed upfront.
607 //
608 // Finally Windows XP added a new flag 'STACK_SIZE_PARAM_IS_A_RESERVATION'
609 // for CreateThread() that can treat 'stack_size' as stack size. However we
610 // are not supposed to call CreateThread() directly according to MSDN
611 // document because JVM uses C runtime library. The good news is that the
612 // flag appears to work with _beginthredex() as well.
613
614 const unsigned initflag = CREATE_SUSPENDED | STACK_SIZE_PARAM_IS_A_RESERVATION;
615 HANDLE thread_handle =
616 (HANDLE)_beginthreadex(NULL,
617 (unsigned)stack_size,
618 (unsigned (__stdcall *)(void*)) thread_native_entry,
619 thread,
620 initflag,
621 &thread_id);
622
623 char buf[64];
624 if (thread_handle != NULL) {
625 log_info(os, thread)("Thread started (tid: %u, attributes: %s)",
626 thread_id, describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
627 } else {
628 log_warning(os, thread)("Failed to start thread - _beginthreadex failed (%s) for attributes: %s.",
629 os::errno_name(errno), describe_beginthreadex_attributes(buf, sizeof(buf), stack_size, initflag));
630 }
631
632 if (thread_handle == NULL) {
633 // Need to clean up stuff we've allocated so far
634 CloseHandle(osthread->interrupt_event());
635 thread->set_osthread(NULL);
636 delete osthread;
637 return NULL;
638 }
639
640 Atomic::inc(&os::win32::_os_thread_count);
641
642 // Store info on the Win32 thread into the OSThread
643 osthread->set_thread_handle(thread_handle);
644 osthread->set_thread_id(thread_id);
645
646 // Initial thread state is INITIALIZED, not SUSPENDED
647 osthread->set_state(INITIALIZED);
648
649 // The thread is returned suspended (in state INITIALIZED), and is started higher up in the call chain
650 return true;
651 }
652
653
654 // Free Win32 resources related to the OSThread
655 void os::free_thread(OSThread* osthread) {
656 assert(osthread != NULL, "osthread not set");
657
658 // We are told to free resources of the argument thread,
659 // but we can only really operate on the current thread.
660 assert(Thread::current()->osthread() == osthread,
661 "os::free_thread but not current thread");
662
663 CloseHandle(osthread->thread_handle());
664 CloseHandle(osthread->interrupt_event());
665 delete osthread;
666 }
667
668 static jlong first_filetime;
669 static jlong initial_performance_count;
670 static jlong performance_frequency;
671
672
673 jlong as_long(LARGE_INTEGER x) {
674 jlong result = 0; // initialization to avoid warning
675 set_high(&result, x.HighPart);
676 set_low(&result, x.LowPart);
677 return result;
678 }
679
680
681 jlong os::elapsed_counter() {
682 LARGE_INTEGER count;
683 QueryPerformanceCounter(&count);
684 return as_long(count) - initial_performance_count;
685 }
686
687
688 jlong os::elapsed_frequency() {
689 return performance_frequency;
690 }
691
692
693 julong os::available_memory() {
694 return win32::available_memory();
695 }
696
697 julong os::win32::available_memory() {
698 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
699 // value if total memory is larger than 4GB
700 MEMORYSTATUSEX ms;
701 ms.dwLength = sizeof(ms);
702 GlobalMemoryStatusEx(&ms);
703
704 return (julong)ms.ullAvailPhys;
705 }
706
707 julong os::physical_memory() {
708 return win32::physical_memory();
709 }
710
711 bool os::has_allocatable_memory_limit(julong* limit) {
712 MEMORYSTATUSEX ms;
713 ms.dwLength = sizeof(ms);
714 GlobalMemoryStatusEx(&ms);
715 #ifdef _LP64
716 *limit = (julong)ms.ullAvailVirtual;
717 return true;
718 #else
719 // Limit to 1400m because of the 2gb address space wall
720 *limit = MIN2((julong)1400*M, (julong)ms.ullAvailVirtual);
721 return true;
722 #endif
723 }
724
725 int os::active_processor_count() {
726 // User has overridden the number of active processors
727 if (ActiveProcessorCount > 0) {
728 log_trace(os)("active_processor_count: "
729 "active processor count set by user : %d",
730 ActiveProcessorCount);
731 return ActiveProcessorCount;
732 }
733
734 DWORD_PTR lpProcessAffinityMask = 0;
735 DWORD_PTR lpSystemAffinityMask = 0;
736 int proc_count = processor_count();
737 if (proc_count <= sizeof(UINT_PTR) * BitsPerByte &&
738 GetProcessAffinityMask(GetCurrentProcess(), &lpProcessAffinityMask, &lpSystemAffinityMask)) {
739 // Nof active processors is number of bits in process affinity mask
740 int bitcount = 0;
741 while (lpProcessAffinityMask != 0) {
742 lpProcessAffinityMask = lpProcessAffinityMask & (lpProcessAffinityMask-1);
743 bitcount++;
744 }
745 return bitcount;
746 } else {
747 return proc_count;
748 }
749 }
750
751 void os::set_native_thread_name(const char *name) {
752
753 // See: http://msdn.microsoft.com/en-us/library/xcb2z8hs.aspx
754 //
755 // Note that unfortunately this only works if the process
756 // is already attached to a debugger; debugger must observe
757 // the exception below to show the correct name.
758
759 // If there is no debugger attached skip raising the exception
760 if (!IsDebuggerPresent()) {
761 return;
762 }
763
764 const DWORD MS_VC_EXCEPTION = 0x406D1388;
765 struct {
766 DWORD dwType; // must be 0x1000
767 LPCSTR szName; // pointer to name (in user addr space)
768 DWORD dwThreadID; // thread ID (-1=caller thread)
769 DWORD dwFlags; // reserved for future use, must be zero
770 } info;
771
772 info.dwType = 0x1000;
773 info.szName = name;
774 info.dwThreadID = -1;
775 info.dwFlags = 0;
776
777 __try {
778 RaiseException (MS_VC_EXCEPTION, 0, sizeof(info)/sizeof(DWORD), (const ULONG_PTR*)&info );
779 } __except(EXCEPTION_EXECUTE_HANDLER) {}
780 }
781
782 bool os::distribute_processes(uint length, uint* distribution) {
783 // Not yet implemented.
784 return false;
785 }
786
787 bool os::bind_to_processor(uint processor_id) {
788 // Not yet implemented.
789 return false;
790 }
791
792 void os::win32::initialize_performance_counter() {
793 LARGE_INTEGER count;
794 QueryPerformanceFrequency(&count);
795 performance_frequency = as_long(count);
796 QueryPerformanceCounter(&count);
797 initial_performance_count = as_long(count);
798 }
799
800
801 double os::elapsedTime() {
802 return (double) elapsed_counter() / (double) elapsed_frequency();
803 }
804
805
806 // Windows format:
807 // The FILETIME structure is a 64-bit value representing the number of 100-nanosecond intervals since January 1, 1601.
808 // Java format:
809 // Java standards require the number of milliseconds since 1/1/1970
810
811 // Constant offset - calculated using offset()
812 static jlong _offset = 116444736000000000;
813 // Fake time counter for reproducible results when debugging
814 static jlong fake_time = 0;
815
816 #ifdef ASSERT
817 // Just to be safe, recalculate the offset in debug mode
818 static jlong _calculated_offset = 0;
819 static int _has_calculated_offset = 0;
820
821 jlong offset() {
822 if (_has_calculated_offset) return _calculated_offset;
823 SYSTEMTIME java_origin;
824 java_origin.wYear = 1970;
825 java_origin.wMonth = 1;
826 java_origin.wDayOfWeek = 0; // ignored
827 java_origin.wDay = 1;
828 java_origin.wHour = 0;
829 java_origin.wMinute = 0;
830 java_origin.wSecond = 0;
831 java_origin.wMilliseconds = 0;
832 FILETIME jot;
833 if (!SystemTimeToFileTime(&java_origin, &jot)) {
834 fatal("Error = %d\nWindows error", GetLastError());
835 }
836 _calculated_offset = jlong_from(jot.dwHighDateTime, jot.dwLowDateTime);
837 _has_calculated_offset = 1;
838 assert(_calculated_offset == _offset, "Calculated and constant time offsets must be equal");
839 return _calculated_offset;
840 }
841 #else
842 jlong offset() {
843 return _offset;
844 }
845 #endif
846
847 jlong windows_to_java_time(FILETIME wt) {
848 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
849 return (a - offset()) / 10000;
850 }
851
852 // Returns time ticks in (10th of micro seconds)
853 jlong windows_to_time_ticks(FILETIME wt) {
854 jlong a = jlong_from(wt.dwHighDateTime, wt.dwLowDateTime);
855 return (a - offset());
856 }
857
858 FILETIME java_to_windows_time(jlong l) {
859 jlong a = (l * 10000) + offset();
860 FILETIME result;
861 result.dwHighDateTime = high(a);
862 result.dwLowDateTime = low(a);
863 return result;
864 }
865
866 bool os::supports_vtime() { return true; }
867 bool os::enable_vtime() { return false; }
868 bool os::vtime_enabled() { return false; }
869
870 double os::elapsedVTime() {
871 FILETIME created;
872 FILETIME exited;
873 FILETIME kernel;
874 FILETIME user;
875 if (GetThreadTimes(GetCurrentThread(), &created, &exited, &kernel, &user) != 0) {
876 // the resolution of windows_to_java_time() should be sufficient (ms)
877 return (double) (windows_to_java_time(kernel) + windows_to_java_time(user)) / MILLIUNITS;
878 } else {
879 return elapsedTime();
880 }
881 }
882
883 jlong os::javaTimeMillis() {
884 if (UseFakeTimers) {
885 return fake_time++;
886 } else {
887 FILETIME wt;
888 GetSystemTimeAsFileTime(&wt);
889 return windows_to_java_time(wt);
890 }
891 }
892
893 void os::javaTimeSystemUTC(jlong &seconds, jlong &nanos) {
894 FILETIME wt;
895 GetSystemTimeAsFileTime(&wt);
896 jlong ticks = windows_to_time_ticks(wt); // 10th of micros
897 jlong secs = jlong(ticks / 10000000); // 10000 * 1000
898 seconds = secs;
899 nanos = jlong(ticks - (secs*10000000)) * 100;
900 }
901
902 jlong os::javaTimeNanos() {
903 LARGE_INTEGER current_count;
904 QueryPerformanceCounter(¤t_count);
905 double current = as_long(current_count);
906 double freq = performance_frequency;
907 jlong time = (jlong)((current/freq) * NANOSECS_PER_SEC);
908 return time;
909 }
910
911 void os::javaTimeNanos_info(jvmtiTimerInfo *info_ptr) {
912 jlong freq = performance_frequency;
913 if (freq < NANOSECS_PER_SEC) {
914 // the performance counter is 64 bits and we will
915 // be multiplying it -- so no wrap in 64 bits
916 info_ptr->max_value = ALL_64_BITS;
917 } else if (freq > NANOSECS_PER_SEC) {
918 // use the max value the counter can reach to
919 // determine the max value which could be returned
920 julong max_counter = (julong)ALL_64_BITS;
921 info_ptr->max_value = (jlong)(max_counter / (freq / NANOSECS_PER_SEC));
922 } else {
923 // the performance counter is 64 bits and we will
924 // be using it directly -- so no wrap in 64 bits
925 info_ptr->max_value = ALL_64_BITS;
926 }
927
928 // using a counter, so no skipping
929 info_ptr->may_skip_backward = false;
930 info_ptr->may_skip_forward = false;
931
932 info_ptr->kind = JVMTI_TIMER_ELAPSED; // elapsed not CPU time
933 }
934
935 char* os::local_time_string(char *buf, size_t buflen) {
936 SYSTEMTIME st;
937 GetLocalTime(&st);
938 jio_snprintf(buf, buflen, "%d-%02d-%02d %02d:%02d:%02d",
939 st.wYear, st.wMonth, st.wDay, st.wHour, st.wMinute, st.wSecond);
940 return buf;
941 }
942
943 bool os::getTimesSecs(double* process_real_time,
944 double* process_user_time,
945 double* process_system_time) {
946 HANDLE h_process = GetCurrentProcess();
947 FILETIME create_time, exit_time, kernel_time, user_time;
948 BOOL result = GetProcessTimes(h_process,
949 &create_time,
950 &exit_time,
951 &kernel_time,
952 &user_time);
953 if (result != 0) {
954 FILETIME wt;
955 GetSystemTimeAsFileTime(&wt);
956 jlong rtc_millis = windows_to_java_time(wt);
957 *process_real_time = ((double) rtc_millis) / ((double) MILLIUNITS);
958 *process_user_time =
959 (double) jlong_from(user_time.dwHighDateTime, user_time.dwLowDateTime) / (10 * MICROUNITS);
960 *process_system_time =
961 (double) jlong_from(kernel_time.dwHighDateTime, kernel_time.dwLowDateTime) / (10 * MICROUNITS);
962 return true;
963 } else {
964 return false;
965 }
966 }
967
968 void os::shutdown() {
969 // allow PerfMemory to attempt cleanup of any persistent resources
970 perfMemory_exit();
971
972 // flush buffered output, finish log files
973 ostream_abort();
974
975 // Check for abort hook
976 abort_hook_t abort_hook = Arguments::abort_hook();
977 if (abort_hook != NULL) {
978 abort_hook();
979 }
980 }
981
982
983 static BOOL (WINAPI *_MiniDumpWriteDump)(HANDLE, DWORD, HANDLE, MINIDUMP_TYPE,
984 PMINIDUMP_EXCEPTION_INFORMATION,
985 PMINIDUMP_USER_STREAM_INFORMATION,
986 PMINIDUMP_CALLBACK_INFORMATION);
987
988 static HANDLE dumpFile = NULL;
989
990 // Check if dump file can be created.
991 void os::check_dump_limit(char* buffer, size_t buffsz) {
992 bool status = true;
993 if (!FLAG_IS_DEFAULT(CreateCoredumpOnCrash) && !CreateCoredumpOnCrash) {
994 jio_snprintf(buffer, buffsz, "CreateCoredumpOnCrash is disabled from command line");
995 status = false;
996 }
997
998 #ifndef ASSERT
999 if (!os::win32::is_windows_server() && FLAG_IS_DEFAULT(CreateCoredumpOnCrash)) {
1000 jio_snprintf(buffer, buffsz, "Minidumps are not enabled by default on client versions of Windows");
1001 status = false;
1002 }
1003 #endif
1004
1005 if (status) {
1006 const char* cwd = get_current_directory(NULL, 0);
1007 int pid = current_process_id();
1008 if (cwd != NULL) {
1009 jio_snprintf(buffer, buffsz, "%s\\hs_err_pid%u.mdmp", cwd, pid);
1010 } else {
1011 jio_snprintf(buffer, buffsz, ".\\hs_err_pid%u.mdmp", pid);
1012 }
1013
1014 if (dumpFile == NULL &&
1015 (dumpFile = CreateFile(buffer, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL))
1016 == INVALID_HANDLE_VALUE) {
1017 jio_snprintf(buffer, buffsz, "Failed to create minidump file (0x%x).", GetLastError());
1018 status = false;
1019 }
1020 }
1021 VMError::record_coredump_status(buffer, status);
1022 }
1023
1024 void os::abort(bool dump_core, void* siginfo, const void* context) {
1025 EXCEPTION_POINTERS ep;
1026 MINIDUMP_EXCEPTION_INFORMATION mei;
1027 MINIDUMP_EXCEPTION_INFORMATION* pmei;
1028
1029 HANDLE hProcess = GetCurrentProcess();
1030 DWORD processId = GetCurrentProcessId();
1031 MINIDUMP_TYPE dumpType;
1032
1033 shutdown();
1034 if (!dump_core || dumpFile == NULL) {
1035 if (dumpFile != NULL) {
1036 CloseHandle(dumpFile);
1037 }
1038 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1039 }
1040
1041 dumpType = (MINIDUMP_TYPE)(MiniDumpWithFullMemory | MiniDumpWithHandleData |
1042 MiniDumpWithFullMemoryInfo | MiniDumpWithThreadInfo | MiniDumpWithUnloadedModules);
1043
1044 if (siginfo != NULL && context != NULL) {
1045 ep.ContextRecord = (PCONTEXT) context;
1046 ep.ExceptionRecord = (PEXCEPTION_RECORD) siginfo;
1047
1048 mei.ThreadId = GetCurrentThreadId();
1049 mei.ExceptionPointers = &ep;
1050 pmei = &mei;
1051 } else {
1052 pmei = NULL;
1053 }
1054
1055 // Older versions of dbghelp.dll (the one shipped with Win2003 for example) may not support all
1056 // the dump types we really want. If first call fails, lets fall back to just use MiniDumpWithFullMemory then.
1057 if (!WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, dumpType, pmei, NULL, NULL) &&
1058 !WindowsDbgHelp::miniDumpWriteDump(hProcess, processId, dumpFile, (MINIDUMP_TYPE)MiniDumpWithFullMemory, pmei, NULL, NULL)) {
1059 jio_fprintf(stderr, "Call to MiniDumpWriteDump() failed (Error 0x%x)\n", GetLastError());
1060 }
1061 CloseHandle(dumpFile);
1062 win32::exit_process_or_thread(win32::EPT_PROCESS, 1);
1063 }
1064
1065 // Die immediately, no exit hook, no abort hook, no cleanup.
1066 void os::die() {
1067 win32::exit_process_or_thread(win32::EPT_PROCESS_DIE, -1);
1068 }
1069
1070 // Directory routines copied from src/win32/native/java/io/dirent_md.c
1071 // * dirent_md.c 1.15 00/02/02
1072 //
1073 // The declarations for DIR and struct dirent are in jvm_win32.h.
1074
1075 // Caller must have already run dirname through JVM_NativePath, which removes
1076 // duplicate slashes and converts all instances of '/' into '\\'.
1077
1078 DIR * os::opendir(const char *dirname) {
1079 assert(dirname != NULL, "just checking"); // hotspot change
1080 DIR *dirp = (DIR *)malloc(sizeof(DIR), mtInternal);
1081 DWORD fattr; // hotspot change
1082 char alt_dirname[4] = { 0, 0, 0, 0 };
1083
1084 if (dirp == 0) {
1085 errno = ENOMEM;
1086 return 0;
1087 }
1088
1089 // Win32 accepts "\" in its POSIX stat(), but refuses to treat it
1090 // as a directory in FindFirstFile(). We detect this case here and
1091 // prepend the current drive name.
1092 //
1093 if (dirname[1] == '\0' && dirname[0] == '\\') {
1094 alt_dirname[0] = _getdrive() + 'A' - 1;
1095 alt_dirname[1] = ':';
1096 alt_dirname[2] = '\\';
1097 alt_dirname[3] = '\0';
1098 dirname = alt_dirname;
1099 }
1100
1101 dirp->path = (char *)malloc(strlen(dirname) + 5, mtInternal);
1102 if (dirp->path == 0) {
1103 free(dirp);
1104 errno = ENOMEM;
1105 return 0;
1106 }
1107 strcpy(dirp->path, dirname);
1108
1109 fattr = GetFileAttributes(dirp->path);
1110 if (fattr == 0xffffffff) {
1111 free(dirp->path);
1112 free(dirp);
1113 errno = ENOENT;
1114 return 0;
1115 } else if ((fattr & FILE_ATTRIBUTE_DIRECTORY) == 0) {
1116 free(dirp->path);
1117 free(dirp);
1118 errno = ENOTDIR;
1119 return 0;
1120 }
1121
1122 // Append "*.*", or possibly "\\*.*", to path
1123 if (dirp->path[1] == ':' &&
1124 (dirp->path[2] == '\0' ||
1125 (dirp->path[2] == '\\' && dirp->path[3] == '\0'))) {
1126 // No '\\' needed for cases like "Z:" or "Z:\"
1127 strcat(dirp->path, "*.*");
1128 } else {
1129 strcat(dirp->path, "\\*.*");
1130 }
1131
1132 dirp->handle = FindFirstFile(dirp->path, &dirp->find_data);
1133 if (dirp->handle == INVALID_HANDLE_VALUE) {
1134 if (GetLastError() != ERROR_FILE_NOT_FOUND) {
1135 free(dirp->path);
1136 free(dirp);
1137 errno = EACCES;
1138 return 0;
1139 }
1140 }
1141 return dirp;
1142 }
1143
1144 // parameter dbuf unused on Windows
1145 struct dirent * os::readdir(DIR *dirp, dirent *dbuf) {
1146 assert(dirp != NULL, "just checking"); // hotspot change
1147 if (dirp->handle == INVALID_HANDLE_VALUE) {
1148 return 0;
1149 }
1150
1151 strcpy(dirp->dirent.d_name, dirp->find_data.cFileName);
1152
1153 if (!FindNextFile(dirp->handle, &dirp->find_data)) {
1154 if (GetLastError() == ERROR_INVALID_HANDLE) {
1155 errno = EBADF;
1156 return 0;
1157 }
1158 FindClose(dirp->handle);
1159 dirp->handle = INVALID_HANDLE_VALUE;
1160 }
1161
1162 return &dirp->dirent;
1163 }
1164
1165 int os::closedir(DIR *dirp) {
1166 assert(dirp != NULL, "just checking"); // hotspot change
1167 if (dirp->handle != INVALID_HANDLE_VALUE) {
1168 if (!FindClose(dirp->handle)) {
1169 errno = EBADF;
1170 return -1;
1171 }
1172 dirp->handle = INVALID_HANDLE_VALUE;
1173 }
1174 free(dirp->path);
1175 free(dirp);
1176 return 0;
1177 }
1178
1179 // This must be hard coded because it's the system's temporary
1180 // directory not the java application's temp directory, ala java.io.tmpdir.
1181 const char* os::get_temp_directory() {
1182 static char path_buf[MAX_PATH];
1183 if (GetTempPath(MAX_PATH, path_buf) > 0) {
1184 return path_buf;
1185 } else {
1186 path_buf[0] = '\0';
1187 return path_buf;
1188 }
1189 }
1190
1191 // Needs to be in os specific directory because windows requires another
1192 // header file <direct.h>
1193 const char* os::get_current_directory(char *buf, size_t buflen) {
1194 int n = static_cast<int>(buflen);
1195 if (buflen > INT_MAX) n = INT_MAX;
1196 return _getcwd(buf, n);
1197 }
1198
1199 //-----------------------------------------------------------
1200 // Helper functions for fatal error handler
1201 #ifdef _WIN64
1202 // Helper routine which returns true if address in
1203 // within the NTDLL address space.
1204 //
1205 static bool _addr_in_ntdll(address addr) {
1206 HMODULE hmod;
1207 MODULEINFO minfo;
1208
1209 hmod = GetModuleHandle("NTDLL.DLL");
1210 if (hmod == NULL) return false;
1211 if (!GetModuleInformation(GetCurrentProcess(), hmod,
1212 &minfo, sizeof(MODULEINFO))) {
1213 return false;
1214 }
1215
1216 if ((addr >= minfo.lpBaseOfDll) &&
1217 (addr < (address)((uintptr_t)minfo.lpBaseOfDll + (uintptr_t)minfo.SizeOfImage))) {
1218 return true;
1219 } else {
1220 return false;
1221 }
1222 }
1223 #endif
1224
1225 struct _modinfo {
1226 address addr;
1227 char* full_path; // point to a char buffer
1228 int buflen; // size of the buffer
1229 address base_addr;
1230 };
1231
1232 static int _locate_module_by_addr(const char * mod_fname, address base_addr,
1233 address top_address, void * param) {
1234 struct _modinfo *pmod = (struct _modinfo *)param;
1235 if (!pmod) return -1;
1236
1237 if (base_addr <= pmod->addr &&
1238 top_address > pmod->addr) {
1239 // if a buffer is provided, copy path name to the buffer
1240 if (pmod->full_path) {
1241 jio_snprintf(pmod->full_path, pmod->buflen, "%s", mod_fname);
1242 }
1243 pmod->base_addr = base_addr;
1244 return 1;
1245 }
1246 return 0;
1247 }
1248
1249 bool os::dll_address_to_library_name(address addr, char* buf,
1250 int buflen, int* offset) {
1251 // buf is not optional, but offset is optional
1252 assert(buf != NULL, "sanity check");
1253
1254 // NOTE: the reason we don't use SymGetModuleInfo() is it doesn't always
1255 // return the full path to the DLL file, sometimes it returns path
1256 // to the corresponding PDB file (debug info); sometimes it only
1257 // returns partial path, which makes life painful.
1258
1259 struct _modinfo mi;
1260 mi.addr = addr;
1261 mi.full_path = buf;
1262 mi.buflen = buflen;
1263 if (get_loaded_modules_info(_locate_module_by_addr, (void *)&mi)) {
1264 // buf already contains path name
1265 if (offset) *offset = addr - mi.base_addr;
1266 return true;
1267 }
1268
1269 buf[0] = '\0';
1270 if (offset) *offset = -1;
1271 return false;
1272 }
1273
1274 bool os::dll_address_to_function_name(address addr, char *buf,
1275 int buflen, int *offset,
1276 bool demangle) {
1277 // buf is not optional, but offset is optional
1278 assert(buf != NULL, "sanity check");
1279
1280 if (Decoder::decode(addr, buf, buflen, offset, demangle)) {
1281 return true;
1282 }
1283 if (offset != NULL) *offset = -1;
1284 buf[0] = '\0';
1285 return false;
1286 }
1287
1288 // save the start and end address of jvm.dll into param[0] and param[1]
1289 static int _locate_jvm_dll(const char* mod_fname, address base_addr,
1290 address top_address, void * param) {
1291 if (!param) return -1;
1292
1293 if (base_addr <= (address)_locate_jvm_dll &&
1294 top_address > (address)_locate_jvm_dll) {
1295 ((address*)param)[0] = base_addr;
1296 ((address*)param)[1] = top_address;
1297 return 1;
1298 }
1299 return 0;
1300 }
1301
1302 address vm_lib_location[2]; // start and end address of jvm.dll
1303
1304 // check if addr is inside jvm.dll
1305 bool os::address_is_in_vm(address addr) {
1306 if (!vm_lib_location[0] || !vm_lib_location[1]) {
1307 if (!get_loaded_modules_info(_locate_jvm_dll, (void *)vm_lib_location)) {
1308 assert(false, "Can't find jvm module.");
1309 return false;
1310 }
1311 }
1312
1313 return (vm_lib_location[0] <= addr) && (addr < vm_lib_location[1]);
1314 }
1315
1316 // print module info; param is outputStream*
1317 static int _print_module(const char* fname, address base_address,
1318 address top_address, void* param) {
1319 if (!param) return -1;
1320
1321 outputStream* st = (outputStream*)param;
1322
1323 st->print(PTR_FORMAT " - " PTR_FORMAT " \t%s\n", base_address, top_address, fname);
1324 return 0;
1325 }
1326
1327 // Loads .dll/.so and
1328 // in case of error it checks if .dll/.so was built for the
1329 // same architecture as Hotspot is running on
1330 void * os::dll_load(const char *name, char *ebuf, int ebuflen) {
1331 void * result = LoadLibrary(name);
1332 if (result != NULL) {
1333 // Recalculate pdb search path if a DLL was loaded successfully.
1334 SymbolEngine::recalc_search_path();
1335 return result;
1336 }
1337
1338 DWORD errcode = GetLastError();
1339 if (errcode == ERROR_MOD_NOT_FOUND) {
1340 strncpy(ebuf, "Can't find dependent libraries", ebuflen - 1);
1341 ebuf[ebuflen - 1] = '\0';
1342 return NULL;
1343 }
1344
1345 // Parsing dll below
1346 // If we can read dll-info and find that dll was built
1347 // for an architecture other than Hotspot is running in
1348 // - then print to buffer "DLL was built for a different architecture"
1349 // else call os::lasterror to obtain system error message
1350
1351 // Read system error message into ebuf
1352 // It may or may not be overwritten below (in the for loop and just above)
1353 lasterror(ebuf, (size_t) ebuflen);
1354 ebuf[ebuflen - 1] = '\0';
1355 int fd = ::open(name, O_RDONLY | O_BINARY, 0);
1356 if (fd < 0) {
1357 return NULL;
1358 }
1359
1360 uint32_t signature_offset;
1361 uint16_t lib_arch = 0;
1362 bool failed_to_get_lib_arch =
1363 ( // Go to position 3c in the dll
1364 (os::seek_to_file_offset(fd, IMAGE_FILE_PTR_TO_SIGNATURE) < 0)
1365 ||
1366 // Read location of signature
1367 (sizeof(signature_offset) !=
1368 (os::read(fd, (void*)&signature_offset, sizeof(signature_offset))))
1369 ||
1370 // Go to COFF File Header in dll
1371 // that is located after "signature" (4 bytes long)
1372 (os::seek_to_file_offset(fd,
1373 signature_offset + IMAGE_FILE_SIGNATURE_LENGTH) < 0)
1374 ||
1375 // Read field that contains code of architecture
1376 // that dll was built for
1377 (sizeof(lib_arch) != (os::read(fd, (void*)&lib_arch, sizeof(lib_arch))))
1378 );
1379
1380 ::close(fd);
1381 if (failed_to_get_lib_arch) {
1382 // file i/o error - report os::lasterror(...) msg
1383 return NULL;
1384 }
1385
1386 typedef struct {
1387 uint16_t arch_code;
1388 char* arch_name;
1389 } arch_t;
1390
1391 static const arch_t arch_array[] = {
1392 {IMAGE_FILE_MACHINE_I386, (char*)"IA 32"},
1393 {IMAGE_FILE_MACHINE_AMD64, (char*)"AMD 64"}
1394 };
1395 #if (defined _M_AMD64)
1396 static const uint16_t running_arch = IMAGE_FILE_MACHINE_AMD64;
1397 #elif (defined _M_IX86)
1398 static const uint16_t running_arch = IMAGE_FILE_MACHINE_I386;
1399 #else
1400 #error Method os::dll_load requires that one of following \
1401 is defined :_M_AMD64 or _M_IX86
1402 #endif
1403
1404
1405 // Obtain a string for printf operation
1406 // lib_arch_str shall contain string what platform this .dll was built for
1407 // running_arch_str shall string contain what platform Hotspot was built for
1408 char *running_arch_str = NULL, *lib_arch_str = NULL;
1409 for (unsigned int i = 0; i < ARRAY_SIZE(arch_array); i++) {
1410 if (lib_arch == arch_array[i].arch_code) {
1411 lib_arch_str = arch_array[i].arch_name;
1412 }
1413 if (running_arch == arch_array[i].arch_code) {
1414 running_arch_str = arch_array[i].arch_name;
1415 }
1416 }
1417
1418 assert(running_arch_str,
1419 "Didn't find running architecture code in arch_array");
1420
1421 // If the architecture is right
1422 // but some other error took place - report os::lasterror(...) msg
1423 if (lib_arch == running_arch) {
1424 return NULL;
1425 }
1426
1427 if (lib_arch_str != NULL) {
1428 ::_snprintf(ebuf, ebuflen - 1,
1429 "Can't load %s-bit .dll on a %s-bit platform",
1430 lib_arch_str, running_arch_str);
1431 } else {
1432 // don't know what architecture this dll was build for
1433 ::_snprintf(ebuf, ebuflen - 1,
1434 "Can't load this .dll (machine code=0x%x) on a %s-bit platform",
1435 lib_arch, running_arch_str);
1436 }
1437
1438 return NULL;
1439 }
1440
1441 void os::print_dll_info(outputStream *st) {
1442 st->print_cr("Dynamic libraries:");
1443 get_loaded_modules_info(_print_module, (void *)st);
1444 }
1445
1446 int os::get_loaded_modules_info(os::LoadedModulesCallbackFunc callback, void *param) {
1447 HANDLE hProcess;
1448
1449 # define MAX_NUM_MODULES 128
1450 HMODULE modules[MAX_NUM_MODULES];
1451 static char filename[MAX_PATH];
1452 int result = 0;
1453
1454 int pid = os::current_process_id();
1455 hProcess = OpenProcess(PROCESS_QUERY_INFORMATION | PROCESS_VM_READ,
1456 FALSE, pid);
1457 if (hProcess == NULL) return 0;
1458
1459 DWORD size_needed;
1460 if (!EnumProcessModules(hProcess, modules, sizeof(modules), &size_needed)) {
1461 CloseHandle(hProcess);
1462 return 0;
1463 }
1464
1465 // number of modules that are currently loaded
1466 int num_modules = size_needed / sizeof(HMODULE);
1467
1468 for (int i = 0; i < MIN2(num_modules, MAX_NUM_MODULES); i++) {
1469 // Get Full pathname:
1470 if (!GetModuleFileNameEx(hProcess, modules[i], filename, sizeof(filename))) {
1471 filename[0] = '\0';
1472 }
1473
1474 MODULEINFO modinfo;
1475 if (!GetModuleInformation(hProcess, modules[i], &modinfo, sizeof(modinfo))) {
1476 modinfo.lpBaseOfDll = NULL;
1477 modinfo.SizeOfImage = 0;
1478 }
1479
1480 // Invoke callback function
1481 result = callback(filename, (address)modinfo.lpBaseOfDll,
1482 (address)((u8)modinfo.lpBaseOfDll + (u8)modinfo.SizeOfImage), param);
1483 if (result) break;
1484 }
1485
1486 CloseHandle(hProcess);
1487 return result;
1488 }
1489
1490 bool os::get_host_name(char* buf, size_t buflen) {
1491 DWORD size = (DWORD)buflen;
1492 return (GetComputerNameEx(ComputerNameDnsHostname, buf, &size) == TRUE);
1493 }
1494
1495 void os::get_summary_os_info(char* buf, size_t buflen) {
1496 stringStream sst(buf, buflen);
1497 os::win32::print_windows_version(&sst);
1498 // chop off newline character
1499 char* nl = strchr(buf, '\n');
1500 if (nl != NULL) *nl = '\0';
1501 }
1502
1503 int os::log_vsnprintf(char* buf, size_t len, const char* fmt, va_list args) {
1504 int ret = vsnprintf(buf, len, fmt, args);
1505 // Get the correct buffer size if buf is too small
1506 if (ret < 0) {
1507 return _vscprintf(fmt, args);
1508 }
1509 return ret;
1510 }
1511
1512 static inline time_t get_mtime(const char* filename) {
1513 struct stat st;
1514 int ret = os::stat(filename, &st);
1515 assert(ret == 0, "failed to stat() file '%s': %s", filename, strerror(errno));
1516 return st.st_mtime;
1517 }
1518
1519 int os::compare_file_modified_times(const char* file1, const char* file2) {
1520 time_t t1 = get_mtime(file1);
1521 time_t t2 = get_mtime(file2);
1522 return t1 - t2;
1523 }
1524
1525 void os::print_os_info_brief(outputStream* st) {
1526 os::print_os_info(st);
1527 }
1528
1529 void os::print_os_info(outputStream* st) {
1530 #ifdef ASSERT
1531 char buffer[1024];
1532 st->print("HostName: ");
1533 if (get_host_name(buffer, sizeof(buffer))) {
1534 st->print("%s ", buffer);
1535 } else {
1536 st->print("N/A ");
1537 }
1538 #endif
1539 st->print("OS:");
1540 os::win32::print_windows_version(st);
1541 }
1542
1543 void os::win32::print_windows_version(outputStream* st) {
1544 OSVERSIONINFOEX osvi;
1545 VS_FIXEDFILEINFO *file_info;
1546 TCHAR kernel32_path[MAX_PATH];
1547 UINT len, ret;
1548
1549 // Use the GetVersionEx information to see if we're on a server or
1550 // workstation edition of Windows. Starting with Windows 8.1 we can't
1551 // trust the OS version information returned by this API.
1552 ZeroMemory(&osvi, sizeof(OSVERSIONINFOEX));
1553 osvi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
1554 if (!GetVersionEx((OSVERSIONINFO *)&osvi)) {
1555 st->print_cr("Call to GetVersionEx failed");
1556 return;
1557 }
1558 bool is_workstation = (osvi.wProductType == VER_NT_WORKSTATION);
1559
1560 // Get the full path to \Windows\System32\kernel32.dll and use that for
1561 // determining what version of Windows we're running on.
1562 len = MAX_PATH - (UINT)strlen("\\kernel32.dll") - 1;
1563 ret = GetSystemDirectory(kernel32_path, len);
1564 if (ret == 0 || ret > len) {
1565 st->print_cr("Call to GetSystemDirectory failed");
1566 return;
1567 }
1568 strncat(kernel32_path, "\\kernel32.dll", MAX_PATH - ret);
1569
1570 DWORD version_size = GetFileVersionInfoSize(kernel32_path, NULL);
1571 if (version_size == 0) {
1572 st->print_cr("Call to GetFileVersionInfoSize failed");
1573 return;
1574 }
1575
1576 LPTSTR version_info = (LPTSTR)os::malloc(version_size, mtInternal);
1577 if (version_info == NULL) {
1578 st->print_cr("Failed to allocate version_info");
1579 return;
1580 }
1581
1582 if (!GetFileVersionInfo(kernel32_path, NULL, version_size, version_info)) {
1583 os::free(version_info);
1584 st->print_cr("Call to GetFileVersionInfo failed");
1585 return;
1586 }
1587
1588 if (!VerQueryValue(version_info, TEXT("\\"), (LPVOID*)&file_info, &len)) {
1589 os::free(version_info);
1590 st->print_cr("Call to VerQueryValue failed");
1591 return;
1592 }
1593
1594 int major_version = HIWORD(file_info->dwProductVersionMS);
1595 int minor_version = LOWORD(file_info->dwProductVersionMS);
1596 int build_number = HIWORD(file_info->dwProductVersionLS);
1597 int build_minor = LOWORD(file_info->dwProductVersionLS);
1598 int os_vers = major_version * 1000 + minor_version;
1599 os::free(version_info);
1600
1601 st->print(" Windows ");
1602 switch (os_vers) {
1603
1604 case 6000:
1605 if (is_workstation) {
1606 st->print("Vista");
1607 } else {
1608 st->print("Server 2008");
1609 }
1610 break;
1611
1612 case 6001:
1613 if (is_workstation) {
1614 st->print("7");
1615 } else {
1616 st->print("Server 2008 R2");
1617 }
1618 break;
1619
1620 case 6002:
1621 if (is_workstation) {
1622 st->print("8");
1623 } else {
1624 st->print("Server 2012");
1625 }
1626 break;
1627
1628 case 6003:
1629 if (is_workstation) {
1630 st->print("8.1");
1631 } else {
1632 st->print("Server 2012 R2");
1633 }
1634 break;
1635
1636 case 10000:
1637 if (is_workstation) {
1638 st->print("10");
1639 } else {
1640 st->print("Server 2016");
1641 }
1642 break;
1643
1644 default:
1645 // Unrecognized windows, print out its major and minor versions
1646 st->print("%d.%d", major_version, minor_version);
1647 break;
1648 }
1649
1650 // Retrieve SYSTEM_INFO from GetNativeSystemInfo call so that we could
1651 // find out whether we are running on 64 bit processor or not
1652 SYSTEM_INFO si;
1653 ZeroMemory(&si, sizeof(SYSTEM_INFO));
1654 GetNativeSystemInfo(&si);
1655 if (si.wProcessorArchitecture == PROCESSOR_ARCHITECTURE_AMD64) {
1656 st->print(" , 64 bit");
1657 }
1658
1659 st->print(" Build %d", build_number);
1660 st->print(" (%d.%d.%d.%d)", major_version, minor_version, build_number, build_minor);
1661 st->cr();
1662 }
1663
1664 void os::pd_print_cpu_info(outputStream* st, char* buf, size_t buflen) {
1665 // Nothing to do for now.
1666 }
1667
1668 void os::get_summary_cpu_info(char* buf, size_t buflen) {
1669 HKEY key;
1670 DWORD status = RegOpenKey(HKEY_LOCAL_MACHINE,
1671 "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", &key);
1672 if (status == ERROR_SUCCESS) {
1673 DWORD size = (DWORD)buflen;
1674 status = RegQueryValueEx(key, "ProcessorNameString", NULL, NULL, (byte*)buf, &size);
1675 if (status != ERROR_SUCCESS) {
1676 strncpy(buf, "## __CPU__", buflen);
1677 }
1678 RegCloseKey(key);
1679 } else {
1680 // Put generic cpu info to return
1681 strncpy(buf, "## __CPU__", buflen);
1682 }
1683 }
1684
1685 void os::print_memory_info(outputStream* st) {
1686 st->print("Memory:");
1687 st->print(" %dk page", os::vm_page_size()>>10);
1688
1689 // Use GlobalMemoryStatusEx() because GlobalMemoryStatus() may return incorrect
1690 // value if total memory is larger than 4GB
1691 MEMORYSTATUSEX ms;
1692 ms.dwLength = sizeof(ms);
1693 GlobalMemoryStatusEx(&ms);
1694
1695 st->print(", physical %uk", os::physical_memory() >> 10);
1696 st->print("(%uk free)", os::available_memory() >> 10);
1697
1698 st->print(", swap %uk", ms.ullTotalPageFile >> 10);
1699 st->print("(%uk free)", ms.ullAvailPageFile >> 10);
1700 st->cr();
1701 }
1702
1703 void os::print_siginfo(outputStream *st, const void* siginfo) {
1704 const EXCEPTION_RECORD* const er = (EXCEPTION_RECORD*)siginfo;
1705 st->print("siginfo:");
1706
1707 char tmp[64];
1708 if (os::exception_name(er->ExceptionCode, tmp, sizeof(tmp)) == NULL) {
1709 strcpy(tmp, "EXCEPTION_??");
1710 }
1711 st->print(" %s (0x%x)", tmp, er->ExceptionCode);
1712
1713 if ((er->ExceptionCode == EXCEPTION_ACCESS_VIOLATION ||
1714 er->ExceptionCode == EXCEPTION_IN_PAGE_ERROR) &&
1715 er->NumberParameters >= 2) {
1716 switch (er->ExceptionInformation[0]) {
1717 case 0: st->print(", reading address"); break;
1718 case 1: st->print(", writing address"); break;
1719 case 8: st->print(", data execution prevention violation at address"); break;
1720 default: st->print(", ExceptionInformation=" INTPTR_FORMAT,
1721 er->ExceptionInformation[0]);
1722 }
1723 st->print(" " INTPTR_FORMAT, er->ExceptionInformation[1]);
1724 } else {
1725 int num = er->NumberParameters;
1726 if (num > 0) {
1727 st->print(", ExceptionInformation=");
1728 for (int i = 0; i < num; i++) {
1729 st->print(INTPTR_FORMAT " ", er->ExceptionInformation[i]);
1730 }
1731 }
1732 }
1733 st->cr();
1734 }
1735
1736 void os::print_signal_handlers(outputStream* st, char* buf, size_t buflen) {
1737 // do nothing
1738 }
1739
1740 static char saved_jvm_path[MAX_PATH] = {0};
1741
1742 // Find the full path to the current module, jvm.dll
1743 void os::jvm_path(char *buf, jint buflen) {
1744 // Error checking.
1745 if (buflen < MAX_PATH) {
1746 assert(false, "must use a large-enough buffer");
1747 buf[0] = '\0';
1748 return;
1749 }
1750 // Lazy resolve the path to current module.
1751 if (saved_jvm_path[0] != 0) {
1752 strcpy(buf, saved_jvm_path);
1753 return;
1754 }
1755
1756 buf[0] = '\0';
1757 if (Arguments::sun_java_launcher_is_altjvm()) {
1758 // Support for the java launcher's '-XXaltjvm=<path>' option. Check
1759 // for a JAVA_HOME environment variable and fix up the path so it
1760 // looks like jvm.dll is installed there (append a fake suffix
1761 // hotspot/jvm.dll).
1762 char* java_home_var = ::getenv("JAVA_HOME");
1763 if (java_home_var != NULL && java_home_var[0] != 0 &&
1764 strlen(java_home_var) < (size_t)buflen) {
1765 strncpy(buf, java_home_var, buflen);
1766
1767 // determine if this is a legacy image or modules image
1768 // modules image doesn't have "jre" subdirectory
1769 size_t len = strlen(buf);
1770 char* jrebin_p = buf + len;
1771 jio_snprintf(jrebin_p, buflen-len, "\\jre\\bin\\");
1772 if (0 != _access(buf, 0)) {
1773 jio_snprintf(jrebin_p, buflen-len, "\\bin\\");
1774 }
1775 len = strlen(buf);
1776 jio_snprintf(buf + len, buflen-len, "hotspot\\jvm.dll");
1777 }
1778 }
1779
1780 if (buf[0] == '\0') {
1781 GetModuleFileName(vm_lib_handle, buf, buflen);
1782 }
1783 strncpy(saved_jvm_path, buf, MAX_PATH);
1784 saved_jvm_path[MAX_PATH - 1] = '\0';
1785 }
1786
1787
1788 void os::print_jni_name_prefix_on(outputStream* st, int args_size) {
1789 #ifndef _WIN64
1790 st->print("_");
1791 #endif
1792 }
1793
1794
1795 void os::print_jni_name_suffix_on(outputStream* st, int args_size) {
1796 #ifndef _WIN64
1797 st->print("@%d", args_size * sizeof(int));
1798 #endif
1799 }
1800
1801 // This method is a copy of JDK's sysGetLastErrorString
1802 // from src/windows/hpi/src/system_md.c
1803
1804 size_t os::lasterror(char* buf, size_t len) {
1805 DWORD errval;
1806
1807 if ((errval = GetLastError()) != 0) {
1808 // DOS error
1809 size_t n = (size_t)FormatMessage(
1810 FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS,
1811 NULL,
1812 errval,
1813 0,
1814 buf,
1815 (DWORD)len,
1816 NULL);
1817 if (n > 3) {
1818 // Drop final '.', CR, LF
1819 if (buf[n - 1] == '\n') n--;
1820 if (buf[n - 1] == '\r') n--;
1821 if (buf[n - 1] == '.') n--;
1822 buf[n] = '\0';
1823 }
1824 return n;
1825 }
1826
1827 if (errno != 0) {
1828 // C runtime error that has no corresponding DOS error code
1829 const char* s = os::strerror(errno);
1830 size_t n = strlen(s);
1831 if (n >= len) n = len - 1;
1832 strncpy(buf, s, n);
1833 buf[n] = '\0';
1834 return n;
1835 }
1836
1837 return 0;
1838 }
1839
1840 int os::get_last_error() {
1841 DWORD error = GetLastError();
1842 if (error == 0) {
1843 error = errno;
1844 }
1845 return (int)error;
1846 }
1847
1848 WindowsSemaphore::WindowsSemaphore(uint value) {
1849 _semaphore = ::CreateSemaphore(NULL, value, LONG_MAX, NULL);
1850
1851 guarantee(_semaphore != NULL, "CreateSemaphore failed with error code: %lu", GetLastError());
1852 }
1853
1854 WindowsSemaphore::~WindowsSemaphore() {
1855 ::CloseHandle(_semaphore);
1856 }
1857
1858 void WindowsSemaphore::signal(uint count) {
1859 if (count > 0) {
1860 BOOL ret = ::ReleaseSemaphore(_semaphore, count, NULL);
1861
1862 assert(ret != 0, "ReleaseSemaphore failed with error code: %lu", GetLastError());
1863 }
1864 }
1865
1866 void WindowsSemaphore::wait() {
1867 DWORD ret = ::WaitForSingleObject(_semaphore, INFINITE);
1868 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1869 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject failed with return value: %lu", ret);
1870 }
1871
1872 bool WindowsSemaphore::trywait() {
1873 DWORD ret = ::WaitForSingleObject(_semaphore, 0);
1874 assert(ret != WAIT_FAILED, "WaitForSingleObject failed with error code: %lu", GetLastError());
1875 return ret == WAIT_OBJECT_0;
1876 }
1877
1878 // sun.misc.Signal
1879 // NOTE that this is a workaround for an apparent kernel bug where if
1880 // a signal handler for SIGBREAK is installed then that signal handler
1881 // takes priority over the console control handler for CTRL_CLOSE_EVENT.
1882 // See bug 4416763.
1883 static void (*sigbreakHandler)(int) = NULL;
1884
1885 static void UserHandler(int sig, void *siginfo, void *context) {
1886 os::signal_notify(sig);
1887 // We need to reinstate the signal handler each time...
1888 os::signal(sig, (void*)UserHandler);
1889 }
1890
1891 void* os::user_handler() {
1892 return (void*) UserHandler;
1893 }
1894
1895 void* os::signal(int signal_number, void* handler) {
1896 if ((signal_number == SIGBREAK) && (!ReduceSignalUsage)) {
1897 void (*oldHandler)(int) = sigbreakHandler;
1898 sigbreakHandler = (void (*)(int)) handler;
1899 return (void*) oldHandler;
1900 } else {
1901 return (void*)::signal(signal_number, (void (*)(int))handler);
1902 }
1903 }
1904
1905 void os::signal_raise(int signal_number) {
1906 raise(signal_number);
1907 }
1908
1909 // The Win32 C runtime library maps all console control events other than ^C
1910 // into SIGBREAK, which makes it impossible to distinguish ^BREAK from close,
1911 // logoff, and shutdown events. We therefore install our own console handler
1912 // that raises SIGTERM for the latter cases.
1913 //
1914 static BOOL WINAPI consoleHandler(DWORD event) {
1915 switch (event) {
1916 case CTRL_C_EVENT:
1917 if (VMError::is_error_reported()) {
1918 // Ctrl-C is pressed during error reporting, likely because the error
1919 // handler fails to abort. Let VM die immediately.
1920 os::die();
1921 }
1922
1923 os::signal_raise(SIGINT);
1924 return TRUE;
1925 break;
1926 case CTRL_BREAK_EVENT:
1927 if (sigbreakHandler != NULL) {
1928 (*sigbreakHandler)(SIGBREAK);
1929 }
1930 return TRUE;
1931 break;
1932 case CTRL_LOGOFF_EVENT: {
1933 // Don't terminate JVM if it is running in a non-interactive session,
1934 // such as a service process.
1935 USEROBJECTFLAGS flags;
1936 HANDLE handle = GetProcessWindowStation();
1937 if (handle != NULL &&
1938 GetUserObjectInformation(handle, UOI_FLAGS, &flags,
1939 sizeof(USEROBJECTFLAGS), NULL)) {
1940 // If it is a non-interactive session, let next handler to deal
1941 // with it.
1942 if ((flags.dwFlags & WSF_VISIBLE) == 0) {
1943 return FALSE;
1944 }
1945 }
1946 }
1947 case CTRL_CLOSE_EVENT:
1948 case CTRL_SHUTDOWN_EVENT:
1949 os::signal_raise(SIGTERM);
1950 return TRUE;
1951 break;
1952 default:
1953 break;
1954 }
1955 return FALSE;
1956 }
1957
1958 // The following code is moved from os.cpp for making this
1959 // code platform specific, which it is by its very nature.
1960
1961 // Return maximum OS signal used + 1 for internal use only
1962 // Used as exit signal for signal_thread
1963 int os::sigexitnum_pd() {
1964 return NSIG;
1965 }
1966
1967 // a counter for each possible signal value, including signal_thread exit signal
1968 static volatile jint pending_signals[NSIG+1] = { 0 };
1969 static HANDLE sig_sem = NULL;
1970
1971 void os::signal_init_pd() {
1972 // Initialize signal structures
1973 memset((void*)pending_signals, 0, sizeof(pending_signals));
1974
1975 sig_sem = ::CreateSemaphore(NULL, 0, NSIG+1, NULL);
1976
1977 // Programs embedding the VM do not want it to attempt to receive
1978 // events like CTRL_LOGOFF_EVENT, which are used to implement the
1979 // shutdown hooks mechanism introduced in 1.3. For example, when
1980 // the VM is run as part of a Windows NT service (i.e., a servlet
1981 // engine in a web server), the correct behavior is for any console
1982 // control handler to return FALSE, not TRUE, because the OS's
1983 // "final" handler for such events allows the process to continue if
1984 // it is a service (while terminating it if it is not a service).
1985 // To make this behavior uniform and the mechanism simpler, we
1986 // completely disable the VM's usage of these console events if -Xrs
1987 // (=ReduceSignalUsage) is specified. This means, for example, that
1988 // the CTRL-BREAK thread dump mechanism is also disabled in this
1989 // case. See bugs 4323062, 4345157, and related bugs.
1990
1991 if (!ReduceSignalUsage) {
1992 // Add a CTRL-C handler
1993 SetConsoleCtrlHandler(consoleHandler, TRUE);
1994 }
1995 }
1996
1997 void os::signal_notify(int signal_number) {
1998 BOOL ret;
1999 if (sig_sem != NULL) {
2000 Atomic::inc(&pending_signals[signal_number]);
2001 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
2002 assert(ret != 0, "ReleaseSemaphore() failed");
2003 }
2004 }
2005
2006 static int check_pending_signals(bool wait_for_signal) {
2007 DWORD ret;
2008 while (true) {
2009 for (int i = 0; i < NSIG + 1; i++) {
2010 jint n = pending_signals[i];
2011 if (n > 0 && n == Atomic::cmpxchg(n - 1, &pending_signals[i], n)) {
2012 return i;
2013 }
2014 }
2015 if (!wait_for_signal) {
2016 return -1;
2017 }
2018
2019 JavaThread *thread = JavaThread::current();
2020
2021 ThreadBlockInVM tbivm(thread);
2022
2023 bool threadIsSuspended;
2024 do {
2025 thread->set_suspend_equivalent();
2026 // cleared by handle_special_suspend_equivalent_condition() or java_suspend_self()
2027 ret = ::WaitForSingleObject(sig_sem, INFINITE);
2028 assert(ret == WAIT_OBJECT_0, "WaitForSingleObject() failed");
2029
2030 // were we externally suspended while we were waiting?
2031 threadIsSuspended = thread->handle_special_suspend_equivalent_condition();
2032 if (threadIsSuspended) {
2033 // The semaphore has been incremented, but while we were waiting
2034 // another thread suspended us. We don't want to continue running
2035 // while suspended because that would surprise the thread that
2036 // suspended us.
2037 ret = ::ReleaseSemaphore(sig_sem, 1, NULL);
2038 assert(ret != 0, "ReleaseSemaphore() failed");
2039
2040 thread->java_suspend_self();
2041 }
2042 } while (threadIsSuspended);
2043 }
2044 }
2045
2046 int os::signal_lookup() {
2047 return check_pending_signals(false);
2048 }
2049
2050 int os::signal_wait() {
2051 return check_pending_signals(true);
2052 }
2053
2054 // Implicit OS exception handling
2055
2056 LONG Handle_Exception(struct _EXCEPTION_POINTERS* exceptionInfo,
2057 address handler) {
2058 JavaThread* thread = (JavaThread*) Thread::current_or_null();
2059 // Save pc in thread
2060 #ifdef _M_AMD64
2061 // Do not blow up if no thread info available.
2062 if (thread) {
2063 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Rip);
2064 }
2065 // Set pc to handler
2066 exceptionInfo->ContextRecord->Rip = (DWORD64)handler;
2067 #else
2068 // Do not blow up if no thread info available.
2069 if (thread) {
2070 thread->set_saved_exception_pc((address)(DWORD_PTR)exceptionInfo->ContextRecord->Eip);
2071 }
2072 // Set pc to handler
2073 exceptionInfo->ContextRecord->Eip = (DWORD)(DWORD_PTR)handler;
2074 #endif
2075
2076 // Continue the execution
2077 return EXCEPTION_CONTINUE_EXECUTION;
2078 }
2079
2080
2081 // Used for PostMortemDump
2082 extern "C" void safepoints();
2083 extern "C" void find(int x);
2084 extern "C" void events();
2085
2086 // According to Windows API documentation, an illegal instruction sequence should generate
2087 // the 0xC000001C exception code. However, real world experience shows that occasionnaly
2088 // the execution of an illegal instruction can generate the exception code 0xC000001E. This
2089 // seems to be an undocumented feature of Win NT 4.0 (and probably other Windows systems).
2090
2091 #define EXCEPTION_ILLEGAL_INSTRUCTION_2 0xC000001E
2092
2093 // From "Execution Protection in the Windows Operating System" draft 0.35
2094 // Once a system header becomes available, the "real" define should be
2095 // included or copied here.
2096 #define EXCEPTION_INFO_EXEC_VIOLATION 0x08
2097
2098 // Windows Vista/2008 heap corruption check
2099 #define EXCEPTION_HEAP_CORRUPTION 0xC0000374
2100
2101 // All Visual C++ exceptions thrown from code generated by the Microsoft Visual
2102 // C++ compiler contain this error code. Because this is a compiler-generated
2103 // error, the code is not listed in the Win32 API header files.
2104 // The code is actually a cryptic mnemonic device, with the initial "E"
2105 // standing for "exception" and the final 3 bytes (0x6D7363) representing the
2106 // ASCII values of "msc".
2107
2108 #define EXCEPTION_UNCAUGHT_CXX_EXCEPTION 0xE06D7363
2109
2110 #define def_excpt(val) { #val, (val) }
2111
2112 static const struct { char* name; uint number; } exceptlabels[] = {
2113 def_excpt(EXCEPTION_ACCESS_VIOLATION),
2114 def_excpt(EXCEPTION_DATATYPE_MISALIGNMENT),
2115 def_excpt(EXCEPTION_BREAKPOINT),
2116 def_excpt(EXCEPTION_SINGLE_STEP),
2117 def_excpt(EXCEPTION_ARRAY_BOUNDS_EXCEEDED),
2118 def_excpt(EXCEPTION_FLT_DENORMAL_OPERAND),
2119 def_excpt(EXCEPTION_FLT_DIVIDE_BY_ZERO),
2120 def_excpt(EXCEPTION_FLT_INEXACT_RESULT),
2121 def_excpt(EXCEPTION_FLT_INVALID_OPERATION),
2122 def_excpt(EXCEPTION_FLT_OVERFLOW),
2123 def_excpt(EXCEPTION_FLT_STACK_CHECK),
2124 def_excpt(EXCEPTION_FLT_UNDERFLOW),
2125 def_excpt(EXCEPTION_INT_DIVIDE_BY_ZERO),
2126 def_excpt(EXCEPTION_INT_OVERFLOW),
2127 def_excpt(EXCEPTION_PRIV_INSTRUCTION),
2128 def_excpt(EXCEPTION_IN_PAGE_ERROR),
2129 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION),
2130 def_excpt(EXCEPTION_ILLEGAL_INSTRUCTION_2),
2131 def_excpt(EXCEPTION_NONCONTINUABLE_EXCEPTION),
2132 def_excpt(EXCEPTION_STACK_OVERFLOW),
2133 def_excpt(EXCEPTION_INVALID_DISPOSITION),
2134 def_excpt(EXCEPTION_GUARD_PAGE),
2135 def_excpt(EXCEPTION_INVALID_HANDLE),
2136 def_excpt(EXCEPTION_UNCAUGHT_CXX_EXCEPTION),
2137 def_excpt(EXCEPTION_HEAP_CORRUPTION)
2138 };
2139
2140 #undef def_excpt
2141
2142 const char* os::exception_name(int exception_code, char *buf, size_t size) {
2143 uint code = static_cast<uint>(exception_code);
2144 for (uint i = 0; i < ARRAY_SIZE(exceptlabels); ++i) {
2145 if (exceptlabels[i].number == code) {
2146 jio_snprintf(buf, size, "%s", exceptlabels[i].name);
2147 return buf;
2148 }
2149 }
2150
2151 return NULL;
2152 }
2153
2154 //-----------------------------------------------------------------------------
2155 LONG Handle_IDiv_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2156 // handle exception caused by idiv; should only happen for -MinInt/-1
2157 // (division by zero is handled explicitly)
2158 #ifdef _M_AMD64
2159 PCONTEXT ctx = exceptionInfo->ContextRecord;
2160 address pc = (address)ctx->Rip;
2161 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && pc[1] == 0xF7 || pc[0] == 0xF7, "not an idiv opcode");
2162 assert(pc[0] >= Assembler::REX && pc[0] <= Assembler::REX_WRXB && (pc[2] & ~0x7) == 0xF8 || (pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2163 if (pc[0] == 0xF7) {
2164 // set correct result values and continue after idiv instruction
2165 ctx->Rip = (DWORD64)pc + 2; // idiv reg, reg is 2 bytes
2166 } else {
2167 ctx->Rip = (DWORD64)pc + 3; // REX idiv reg, reg is 3 bytes
2168 }
2169 // Do not set ctx->Rax as it already contains the correct value (either 32 or 64 bit, depending on the operation)
2170 // this is the case because the exception only happens for -MinValue/-1 and -MinValue is always in rax because of the
2171 // idiv opcode (0xF7).
2172 ctx->Rdx = (DWORD)0; // remainder
2173 // Continue the execution
2174 #else
2175 PCONTEXT ctx = exceptionInfo->ContextRecord;
2176 address pc = (address)ctx->Eip;
2177 assert(pc[0] == 0xF7, "not an idiv opcode");
2178 assert((pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
2179 assert(ctx->Eax == min_jint, "unexpected idiv exception");
2180 // set correct result values and continue after idiv instruction
2181 ctx->Eip = (DWORD)pc + 2; // idiv reg, reg is 2 bytes
2182 ctx->Eax = (DWORD)min_jint; // result
2183 ctx->Edx = (DWORD)0; // remainder
2184 // Continue the execution
2185 #endif
2186 return EXCEPTION_CONTINUE_EXECUTION;
2187 }
2188
2189 //-----------------------------------------------------------------------------
2190 LONG WINAPI Handle_FLT_Exception(struct _EXCEPTION_POINTERS* exceptionInfo) {
2191 PCONTEXT ctx = exceptionInfo->ContextRecord;
2192 #ifndef _WIN64
2193 // handle exception caused by native method modifying control word
2194 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2195
2196 switch (exception_code) {
2197 case EXCEPTION_FLT_DENORMAL_OPERAND:
2198 case EXCEPTION_FLT_DIVIDE_BY_ZERO:
2199 case EXCEPTION_FLT_INEXACT_RESULT:
2200 case EXCEPTION_FLT_INVALID_OPERATION:
2201 case EXCEPTION_FLT_OVERFLOW:
2202 case EXCEPTION_FLT_STACK_CHECK:
2203 case EXCEPTION_FLT_UNDERFLOW:
2204 jint fp_control_word = (* (jint*) StubRoutines::addr_fpu_cntrl_wrd_std());
2205 if (fp_control_word != ctx->FloatSave.ControlWord) {
2206 // Restore FPCW and mask out FLT exceptions
2207 ctx->FloatSave.ControlWord = fp_control_word | 0xffffffc0;
2208 // Mask out pending FLT exceptions
2209 ctx->FloatSave.StatusWord &= 0xffffff00;
2210 return EXCEPTION_CONTINUE_EXECUTION;
2211 }
2212 }
2213
2214 if (prev_uef_handler != NULL) {
2215 // We didn't handle this exception so pass it to the previous
2216 // UnhandledExceptionFilter.
2217 return (prev_uef_handler)(exceptionInfo);
2218 }
2219 #else // !_WIN64
2220 // On Windows, the mxcsr control bits are non-volatile across calls
2221 // See also CR 6192333
2222 //
2223 jint MxCsr = INITIAL_MXCSR;
2224 // we can't use StubRoutines::addr_mxcsr_std()
2225 // because in Win64 mxcsr is not saved there
2226 if (MxCsr != ctx->MxCsr) {
2227 ctx->MxCsr = MxCsr;
2228 return EXCEPTION_CONTINUE_EXECUTION;
2229 }
2230 #endif // !_WIN64
2231
2232 return EXCEPTION_CONTINUE_SEARCH;
2233 }
2234
2235 static inline void report_error(Thread* t, DWORD exception_code,
2236 address addr, void* siginfo, void* context) {
2237 VMError::report_and_die(t, exception_code, addr, siginfo, context);
2238
2239 // If UseOsErrorReporting, this will return here and save the error file
2240 // somewhere where we can find it in the minidump.
2241 }
2242
2243 bool os::win32::get_frame_at_stack_banging_point(JavaThread* thread,
2244 struct _EXCEPTION_POINTERS* exceptionInfo, address pc, frame* fr) {
2245 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2246 address addr = (address) exceptionRecord->ExceptionInformation[1];
2247 if (Interpreter::contains(pc)) {
2248 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2249 if (!fr->is_first_java_frame()) {
2250 // get_frame_at_stack_banging_point() is only called when we
2251 // have well defined stacks so java_sender() calls do not need
2252 // to assert safe_for_sender() first.
2253 *fr = fr->java_sender();
2254 }
2255 } else {
2256 // more complex code with compiled code
2257 assert(!Interpreter::contains(pc), "Interpreted methods should have been handled above");
2258 CodeBlob* cb = CodeCache::find_blob(pc);
2259 if (cb == NULL || !cb->is_nmethod() || cb->is_frame_complete_at(pc)) {
2260 // Not sure where the pc points to, fallback to default
2261 // stack overflow handling
2262 return false;
2263 } else {
2264 *fr = os::fetch_frame_from_context((void*)exceptionInfo->ContextRecord);
2265 // in compiled code, the stack banging is performed just after the return pc
2266 // has been pushed on the stack
2267 *fr = frame(fr->sp() + 1, fr->fp(), (address)*(fr->sp()));
2268 if (!fr->is_java_frame()) {
2269 // See java_sender() comment above.
2270 *fr = fr->java_sender();
2271 }
2272 }
2273 }
2274 assert(fr->is_java_frame(), "Safety check");
2275 return true;
2276 }
2277
2278 //-----------------------------------------------------------------------------
2279 LONG WINAPI topLevelExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2280 if (InterceptOSException) return EXCEPTION_CONTINUE_SEARCH;
2281 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2282 #ifdef _M_AMD64
2283 address pc = (address) exceptionInfo->ContextRecord->Rip;
2284 #else
2285 address pc = (address) exceptionInfo->ContextRecord->Eip;
2286 #endif
2287 Thread* t = Thread::current_or_null_safe();
2288
2289 // Handle SafeFetch32 and SafeFetchN exceptions.
2290 if (StubRoutines::is_safefetch_fault(pc)) {
2291 return Handle_Exception(exceptionInfo, StubRoutines::continuation_for_safefetch_fault(pc));
2292 }
2293
2294 #ifndef _WIN64
2295 // Execution protection violation - win32 running on AMD64 only
2296 // Handled first to avoid misdiagnosis as a "normal" access violation;
2297 // This is safe to do because we have a new/unique ExceptionInformation
2298 // code for this condition.
2299 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2300 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2301 int exception_subcode = (int) exceptionRecord->ExceptionInformation[0];
2302 address addr = (address) exceptionRecord->ExceptionInformation[1];
2303
2304 if (exception_subcode == EXCEPTION_INFO_EXEC_VIOLATION) {
2305 int page_size = os::vm_page_size();
2306
2307 // Make sure the pc and the faulting address are sane.
2308 //
2309 // If an instruction spans a page boundary, and the page containing
2310 // the beginning of the instruction is executable but the following
2311 // page is not, the pc and the faulting address might be slightly
2312 // different - we still want to unguard the 2nd page in this case.
2313 //
2314 // 15 bytes seems to be a (very) safe value for max instruction size.
2315 bool pc_is_near_addr =
2316 (pointer_delta((void*) addr, (void*) pc, sizeof(char)) < 15);
2317 bool instr_spans_page_boundary =
2318 (align_down((intptr_t) pc ^ (intptr_t) addr,
2319 (intptr_t) page_size) > 0);
2320
2321 if (pc == addr || (pc_is_near_addr && instr_spans_page_boundary)) {
2322 static volatile address last_addr =
2323 (address) os::non_memory_address_word();
2324
2325 // In conservative mode, don't unguard unless the address is in the VM
2326 if (UnguardOnExecutionViolation > 0 && addr != last_addr &&
2327 (UnguardOnExecutionViolation > 1 || os::address_is_in_vm(addr))) {
2328
2329 // Set memory to RWX and retry
2330 address page_start = align_down(addr, page_size);
2331 bool res = os::protect_memory((char*) page_start, page_size,
2332 os::MEM_PROT_RWX);
2333
2334 log_debug(os)("Execution protection violation "
2335 "at " INTPTR_FORMAT
2336 ", unguarding " INTPTR_FORMAT ": %s", p2i(addr),
2337 p2i(page_start), (res ? "success" : os::strerror(errno)));
2338
2339 // Set last_addr so if we fault again at the same address, we don't
2340 // end up in an endless loop.
2341 //
2342 // There are two potential complications here. Two threads trapping
2343 // at the same address at the same time could cause one of the
2344 // threads to think it already unguarded, and abort the VM. Likely
2345 // very rare.
2346 //
2347 // The other race involves two threads alternately trapping at
2348 // different addresses and failing to unguard the page, resulting in
2349 // an endless loop. This condition is probably even more unlikely
2350 // than the first.
2351 //
2352 // Although both cases could be avoided by using locks or thread
2353 // local last_addr, these solutions are unnecessary complication:
2354 // this handler is a best-effort safety net, not a complete solution.
2355 // It is disabled by default and should only be used as a workaround
2356 // in case we missed any no-execute-unsafe VM code.
2357
2358 last_addr = addr;
2359
2360 return EXCEPTION_CONTINUE_EXECUTION;
2361 }
2362 }
2363
2364 // Last unguard failed or not unguarding
2365 tty->print_raw_cr("Execution protection violation");
2366 report_error(t, exception_code, addr, exceptionInfo->ExceptionRecord,
2367 exceptionInfo->ContextRecord);
2368 return EXCEPTION_CONTINUE_SEARCH;
2369 }
2370 }
2371 #endif // _WIN64
2372
2373 // Check to see if we caught the safepoint code in the
2374 // process of write protecting the memory serialization page.
2375 // It write enables the page immediately after protecting it
2376 // so just return.
2377 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2378 if (t != NULL && t->is_Java_thread()) {
2379 JavaThread* thread = (JavaThread*) t;
2380 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2381 address addr = (address) exceptionRecord->ExceptionInformation[1];
2382 if (os::is_memory_serialize_page(thread, addr)) {
2383 // Block current thread until the memory serialize page permission restored.
2384 os::block_on_serialize_page_trap();
2385 return EXCEPTION_CONTINUE_EXECUTION;
2386 }
2387 }
2388 }
2389
2390 if ((exception_code == EXCEPTION_ACCESS_VIOLATION) &&
2391 VM_Version::is_cpuinfo_segv_addr(pc)) {
2392 // Verify that OS save/restore AVX registers.
2393 return Handle_Exception(exceptionInfo, VM_Version::cpuinfo_cont_addr());
2394 }
2395
2396 if (t != NULL && t->is_Java_thread()) {
2397 JavaThread* thread = (JavaThread*) t;
2398 bool in_java = thread->thread_state() == _thread_in_Java;
2399
2400 // Handle potential stack overflows up front.
2401 if (exception_code == EXCEPTION_STACK_OVERFLOW) {
2402 if (thread->stack_guards_enabled()) {
2403 if (in_java) {
2404 frame fr;
2405 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2406 address addr = (address) exceptionRecord->ExceptionInformation[1];
2407 if (os::win32::get_frame_at_stack_banging_point(thread, exceptionInfo, pc, &fr)) {
2408 assert(fr.is_java_frame(), "Must be a Java frame");
2409 SharedRuntime::look_for_reserved_stack_annotated_method(thread, fr);
2410 }
2411 }
2412 // Yellow zone violation. The o/s has unprotected the first yellow
2413 // zone page for us. Note: must call disable_stack_yellow_zone to
2414 // update the enabled status, even if the zone contains only one page.
2415 assert(thread->thread_state() != _thread_in_vm, "Undersized StackShadowPages");
2416 thread->disable_stack_yellow_reserved_zone();
2417 // If not in java code, return and hope for the best.
2418 return in_java
2419 ? Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW))
2420 : EXCEPTION_CONTINUE_EXECUTION;
2421 } else {
2422 // Fatal red zone violation.
2423 thread->disable_stack_red_zone();
2424 tty->print_raw_cr("An unrecoverable stack overflow has occurred.");
2425 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2426 exceptionInfo->ContextRecord);
2427 return EXCEPTION_CONTINUE_SEARCH;
2428 }
2429 } else if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2430 // Either stack overflow or null pointer exception.
2431 if (in_java) {
2432 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2433 address addr = (address) exceptionRecord->ExceptionInformation[1];
2434 address stack_end = thread->stack_end();
2435 if (addr < stack_end && addr >= stack_end - os::vm_page_size()) {
2436 // Stack overflow.
2437 assert(!os::uses_stack_guard_pages(),
2438 "should be caught by red zone code above.");
2439 return Handle_Exception(exceptionInfo,
2440 SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::STACK_OVERFLOW));
2441 }
2442 // Check for safepoint polling and implicit null
2443 // We only expect null pointers in the stubs (vtable)
2444 // the rest are checked explicitly now.
2445 CodeBlob* cb = CodeCache::find_blob(pc);
2446 if (cb != NULL) {
2447 if (os::is_poll_address(addr)) {
2448 address stub = SharedRuntime::get_poll_stub(pc);
2449 return Handle_Exception(exceptionInfo, stub);
2450 }
2451 }
2452 {
2453 #ifdef _WIN64
2454 // If it's a legal stack address map the entire region in
2455 //
2456 PEXCEPTION_RECORD exceptionRecord = exceptionInfo->ExceptionRecord;
2457 address addr = (address) exceptionRecord->ExceptionInformation[1];
2458 if (addr > thread->stack_reserved_zone_base() && addr < thread->stack_base()) {
2459 addr = (address)((uintptr_t)addr &
2460 (~((uintptr_t)os::vm_page_size() - (uintptr_t)1)));
2461 os::commit_memory((char *)addr, thread->stack_base() - addr,
2462 !ExecMem);
2463 return EXCEPTION_CONTINUE_EXECUTION;
2464 } else
2465 #endif
2466 {
2467 // Null pointer exception.
2468 if (!MacroAssembler::needs_explicit_null_check((intptr_t)addr)) {
2469 address stub = SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_NULL);
2470 if (stub != NULL) return Handle_Exception(exceptionInfo, stub);
2471 }
2472 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2473 exceptionInfo->ContextRecord);
2474 return EXCEPTION_CONTINUE_SEARCH;
2475 }
2476 }
2477 }
2478
2479 #ifdef _WIN64
2480 // Special care for fast JNI field accessors.
2481 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks
2482 // in and the heap gets shrunk before the field access.
2483 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2484 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2485 if (addr != (address)-1) {
2486 return Handle_Exception(exceptionInfo, addr);
2487 }
2488 }
2489 #endif
2490
2491 // Stack overflow or null pointer exception in native code.
2492 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2493 exceptionInfo->ContextRecord);
2494 return EXCEPTION_CONTINUE_SEARCH;
2495 } // /EXCEPTION_ACCESS_VIOLATION
2496 // - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
2497
2498 if (exception_code == EXCEPTION_IN_PAGE_ERROR) {
2499 CompiledMethod* nm = NULL;
2500 JavaThread* thread = (JavaThread*)t;
2501 if (in_java) {
2502 CodeBlob* cb = CodeCache::find_blob_unsafe(pc);
2503 nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
2504 }
2505 if ((thread->thread_state() == _thread_in_vm &&
2506 thread->doing_unsafe_access()) ||
2507 (nm != NULL && nm->has_unsafe_access())) {
2508 return Handle_Exception(exceptionInfo, SharedRuntime::handle_unsafe_access(thread, (address)Assembler::locate_next_instruction(pc)));
2509 }
2510 }
2511
2512 if (in_java) {
2513 switch (exception_code) {
2514 case EXCEPTION_INT_DIVIDE_BY_ZERO:
2515 return Handle_Exception(exceptionInfo, SharedRuntime::continuation_for_implicit_exception(thread, pc, SharedRuntime::IMPLICIT_DIVIDE_BY_ZERO));
2516
2517 case EXCEPTION_INT_OVERFLOW:
2518 return Handle_IDiv_Exception(exceptionInfo);
2519
2520 } // switch
2521 }
2522 if (((thread->thread_state() == _thread_in_Java) ||
2523 (thread->thread_state() == _thread_in_native)) &&
2524 exception_code != EXCEPTION_UNCAUGHT_CXX_EXCEPTION) {
2525 LONG result=Handle_FLT_Exception(exceptionInfo);
2526 if (result==EXCEPTION_CONTINUE_EXECUTION) return result;
2527 }
2528 }
2529
2530 if (exception_code != EXCEPTION_BREAKPOINT) {
2531 report_error(t, exception_code, pc, exceptionInfo->ExceptionRecord,
2532 exceptionInfo->ContextRecord);
2533 }
2534 return EXCEPTION_CONTINUE_SEARCH;
2535 }
2536
2537 #ifndef _WIN64
2538 // Special care for fast JNI accessors.
2539 // jni_fast_Get<Primitive>Field can trap at certain pc's if a GC kicks in and
2540 // the heap gets shrunk before the field access.
2541 // Need to install our own structured exception handler since native code may
2542 // install its own.
2543 LONG WINAPI fastJNIAccessorExceptionFilter(struct _EXCEPTION_POINTERS* exceptionInfo) {
2544 DWORD exception_code = exceptionInfo->ExceptionRecord->ExceptionCode;
2545 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
2546 address pc = (address) exceptionInfo->ContextRecord->Eip;
2547 address addr = JNI_FastGetField::find_slowcase_pc(pc);
2548 if (addr != (address)-1) {
2549 return Handle_Exception(exceptionInfo, addr);
2550 }
2551 }
2552 return EXCEPTION_CONTINUE_SEARCH;
2553 }
2554
2555 #define DEFINE_FAST_GETFIELD(Return, Fieldname, Result) \
2556 Return JNICALL jni_fast_Get##Result##Field_wrapper(JNIEnv *env, \
2557 jobject obj, \
2558 jfieldID fieldID) { \
2559 __try { \
2560 return (*JNI_FastGetField::jni_fast_Get##Result##Field_fp)(env, \
2561 obj, \
2562 fieldID); \
2563 } __except(fastJNIAccessorExceptionFilter((_EXCEPTION_POINTERS*) \
2564 _exception_info())) { \
2565 } \
2566 return 0; \
2567 }
2568
2569 DEFINE_FAST_GETFIELD(jboolean, bool, Boolean)
2570 DEFINE_FAST_GETFIELD(jbyte, byte, Byte)
2571 DEFINE_FAST_GETFIELD(jchar, char, Char)
2572 DEFINE_FAST_GETFIELD(jshort, short, Short)
2573 DEFINE_FAST_GETFIELD(jint, int, Int)
2574 DEFINE_FAST_GETFIELD(jlong, long, Long)
2575 DEFINE_FAST_GETFIELD(jfloat, float, Float)
2576 DEFINE_FAST_GETFIELD(jdouble, double, Double)
2577
2578 address os::win32::fast_jni_accessor_wrapper(BasicType type) {
2579 switch (type) {
2580 case T_BOOLEAN: return (address)jni_fast_GetBooleanField_wrapper;
2581 case T_BYTE: return (address)jni_fast_GetByteField_wrapper;
2582 case T_CHAR: return (address)jni_fast_GetCharField_wrapper;
2583 case T_SHORT: return (address)jni_fast_GetShortField_wrapper;
2584 case T_INT: return (address)jni_fast_GetIntField_wrapper;
2585 case T_LONG: return (address)jni_fast_GetLongField_wrapper;
2586 case T_FLOAT: return (address)jni_fast_GetFloatField_wrapper;
2587 case T_DOUBLE: return (address)jni_fast_GetDoubleField_wrapper;
2588 default: ShouldNotReachHere();
2589 }
2590 return (address)-1;
2591 }
2592 #endif
2593
2594 // Virtual Memory
2595
2596 int os::vm_page_size() { return os::win32::vm_page_size(); }
2597 int os::vm_allocation_granularity() {
2598 return os::win32::vm_allocation_granularity();
2599 }
2600
2601 // Windows large page support is available on Windows 2003. In order to use
2602 // large page memory, the administrator must first assign additional privilege
2603 // to the user:
2604 // + select Control Panel -> Administrative Tools -> Local Security Policy
2605 // + select Local Policies -> User Rights Assignment
2606 // + double click "Lock pages in memory", add users and/or groups
2607 // + reboot
2608 // Note the above steps are needed for administrator as well, as administrators
2609 // by default do not have the privilege to lock pages in memory.
2610 //
2611 // Note about Windows 2003: although the API supports committing large page
2612 // memory on a page-by-page basis and VirtualAlloc() returns success under this
2613 // scenario, I found through experiment it only uses large page if the entire
2614 // memory region is reserved and committed in a single VirtualAlloc() call.
2615 // This makes Windows large page support more or less like Solaris ISM, in
2616 // that the entire heap must be committed upfront. This probably will change
2617 // in the future, if so the code below needs to be revisited.
2618
2619 #ifndef MEM_LARGE_PAGES
2620 #define MEM_LARGE_PAGES 0x20000000
2621 #endif
2622
2623 static HANDLE _hProcess;
2624 static HANDLE _hToken;
2625
2626 // Container for NUMA node list info
2627 class NUMANodeListHolder {
2628 private:
2629 int *_numa_used_node_list; // allocated below
2630 int _numa_used_node_count;
2631
2632 void free_node_list() {
2633 if (_numa_used_node_list != NULL) {
2634 FREE_C_HEAP_ARRAY(int, _numa_used_node_list);
2635 }
2636 }
2637
2638 public:
2639 NUMANodeListHolder() {
2640 _numa_used_node_count = 0;
2641 _numa_used_node_list = NULL;
2642 // do rest of initialization in build routine (after function pointers are set up)
2643 }
2644
2645 ~NUMANodeListHolder() {
2646 free_node_list();
2647 }
2648
2649 bool build() {
2650 DWORD_PTR proc_aff_mask;
2651 DWORD_PTR sys_aff_mask;
2652 if (!GetProcessAffinityMask(GetCurrentProcess(), &proc_aff_mask, &sys_aff_mask)) return false;
2653 ULONG highest_node_number;
2654 if (!GetNumaHighestNodeNumber(&highest_node_number)) return false;
2655 free_node_list();
2656 _numa_used_node_list = NEW_C_HEAP_ARRAY(int, highest_node_number + 1, mtInternal);
2657 for (unsigned int i = 0; i <= highest_node_number; i++) {
2658 ULONGLONG proc_mask_numa_node;
2659 if (!GetNumaNodeProcessorMask(i, &proc_mask_numa_node)) return false;
2660 if ((proc_aff_mask & proc_mask_numa_node)!=0) {
2661 _numa_used_node_list[_numa_used_node_count++] = i;
2662 }
2663 }
2664 return (_numa_used_node_count > 1);
2665 }
2666
2667 int get_count() { return _numa_used_node_count; }
2668 int get_node_list_entry(int n) {
2669 // for indexes out of range, returns -1
2670 return (n < _numa_used_node_count ? _numa_used_node_list[n] : -1);
2671 }
2672
2673 } numa_node_list_holder;
2674
2675
2676
2677 static size_t _large_page_size = 0;
2678
2679 static bool request_lock_memory_privilege() {
2680 _hProcess = OpenProcess(PROCESS_QUERY_INFORMATION, FALSE,
2681 os::current_process_id());
2682
2683 LUID luid;
2684 if (_hProcess != NULL &&
2685 OpenProcessToken(_hProcess, TOKEN_ADJUST_PRIVILEGES, &_hToken) &&
2686 LookupPrivilegeValue(NULL, "SeLockMemoryPrivilege", &luid)) {
2687
2688 TOKEN_PRIVILEGES tp;
2689 tp.PrivilegeCount = 1;
2690 tp.Privileges[0].Luid = luid;
2691 tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
2692
2693 // AdjustTokenPrivileges() may return TRUE even when it couldn't change the
2694 // privilege. Check GetLastError() too. See MSDN document.
2695 if (AdjustTokenPrivileges(_hToken, false, &tp, sizeof(tp), NULL, NULL) &&
2696 (GetLastError() == ERROR_SUCCESS)) {
2697 return true;
2698 }
2699 }
2700
2701 return false;
2702 }
2703
2704 static void cleanup_after_large_page_init() {
2705 if (_hProcess) CloseHandle(_hProcess);
2706 _hProcess = NULL;
2707 if (_hToken) CloseHandle(_hToken);
2708 _hToken = NULL;
2709 }
2710
2711 static bool numa_interleaving_init() {
2712 bool success = false;
2713 bool use_numa_interleaving_specified = !FLAG_IS_DEFAULT(UseNUMAInterleaving);
2714
2715 // print a warning if UseNUMAInterleaving flag is specified on command line
2716 bool warn_on_failure = use_numa_interleaving_specified;
2717 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2718
2719 // NUMAInterleaveGranularity cannot be less than vm_allocation_granularity (or _large_page_size if using large pages)
2720 size_t min_interleave_granularity = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2721 NUMAInterleaveGranularity = align_up(NUMAInterleaveGranularity, min_interleave_granularity);
2722
2723 if (numa_node_list_holder.build()) {
2724 if (log_is_enabled(Debug, os, cpu)) {
2725 Log(os, cpu) log;
2726 log.debug("NUMA UsedNodeCount=%d, namely ", numa_node_list_holder.get_count());
2727 for (int i = 0; i < numa_node_list_holder.get_count(); i++) {
2728 log.debug(" %d ", numa_node_list_holder.get_node_list_entry(i));
2729 }
2730 }
2731 success = true;
2732 } else {
2733 WARN("Process does not cover multiple NUMA nodes.");
2734 }
2735 if (!success) {
2736 if (use_numa_interleaving_specified) WARN("...Ignoring UseNUMAInterleaving flag.");
2737 }
2738 return success;
2739 #undef WARN
2740 }
2741
2742 // this routine is used whenever we need to reserve a contiguous VA range
2743 // but we need to make separate VirtualAlloc calls for each piece of the range
2744 // Reasons for doing this:
2745 // * UseLargePagesIndividualAllocation was set (normally only needed on WS2003 but possible to be set otherwise)
2746 // * UseNUMAInterleaving requires a separate node for each piece
2747 static char* allocate_pages_individually(size_t bytes, char* addr, DWORD flags,
2748 DWORD prot,
2749 bool should_inject_error = false) {
2750 char * p_buf;
2751 // note: at setup time we guaranteed that NUMAInterleaveGranularity was aligned up to a page size
2752 size_t page_size = UseLargePages ? _large_page_size : os::vm_allocation_granularity();
2753 size_t chunk_size = UseNUMAInterleaving ? NUMAInterleaveGranularity : page_size;
2754
2755 // first reserve enough address space in advance since we want to be
2756 // able to break a single contiguous virtual address range into multiple
2757 // large page commits but WS2003 does not allow reserving large page space
2758 // so we just use 4K pages for reserve, this gives us a legal contiguous
2759 // address space. then we will deallocate that reservation, and re alloc
2760 // using large pages
2761 const size_t size_of_reserve = bytes + chunk_size;
2762 if (bytes > size_of_reserve) {
2763 // Overflowed.
2764 return NULL;
2765 }
2766 p_buf = (char *) VirtualAlloc(addr,
2767 size_of_reserve, // size of Reserve
2768 MEM_RESERVE,
2769 PAGE_READWRITE);
2770 // If reservation failed, return NULL
2771 if (p_buf == NULL) return NULL;
2772 MemTracker::record_virtual_memory_reserve((address)p_buf, size_of_reserve, CALLER_PC);
2773 os::release_memory(p_buf, bytes + chunk_size);
2774
2775 // we still need to round up to a page boundary (in case we are using large pages)
2776 // but not to a chunk boundary (in case InterleavingGranularity doesn't align with page size)
2777 // instead we handle this in the bytes_to_rq computation below
2778 p_buf = align_up(p_buf, page_size);
2779
2780 // now go through and allocate one chunk at a time until all bytes are
2781 // allocated
2782 size_t bytes_remaining = bytes;
2783 // An overflow of align_up() would have been caught above
2784 // in the calculation of size_of_reserve.
2785 char * next_alloc_addr = p_buf;
2786 HANDLE hProc = GetCurrentProcess();
2787
2788 #ifdef ASSERT
2789 // Variable for the failure injection
2790 int ran_num = os::random();
2791 size_t fail_after = ran_num % bytes;
2792 #endif
2793
2794 int count=0;
2795 while (bytes_remaining) {
2796 // select bytes_to_rq to get to the next chunk_size boundary
2797
2798 size_t bytes_to_rq = MIN2(bytes_remaining, chunk_size - ((size_t)next_alloc_addr % chunk_size));
2799 // Note allocate and commit
2800 char * p_new;
2801
2802 #ifdef ASSERT
2803 bool inject_error_now = should_inject_error && (bytes_remaining <= fail_after);
2804 #else
2805 const bool inject_error_now = false;
2806 #endif
2807
2808 if (inject_error_now) {
2809 p_new = NULL;
2810 } else {
2811 if (!UseNUMAInterleaving) {
2812 p_new = (char *) VirtualAlloc(next_alloc_addr,
2813 bytes_to_rq,
2814 flags,
2815 prot);
2816 } else {
2817 // get the next node to use from the used_node_list
2818 assert(numa_node_list_holder.get_count() > 0, "Multiple NUMA nodes expected");
2819 DWORD node = numa_node_list_holder.get_node_list_entry(count % numa_node_list_holder.get_count());
2820 p_new = (char *)VirtualAllocExNuma(hProc, next_alloc_addr, bytes_to_rq, flags, prot, node);
2821 }
2822 }
2823
2824 if (p_new == NULL) {
2825 // Free any allocated pages
2826 if (next_alloc_addr > p_buf) {
2827 // Some memory was committed so release it.
2828 size_t bytes_to_release = bytes - bytes_remaining;
2829 // NMT has yet to record any individual blocks, so it
2830 // need to create a dummy 'reserve' record to match
2831 // the release.
2832 MemTracker::record_virtual_memory_reserve((address)p_buf,
2833 bytes_to_release, CALLER_PC);
2834 os::release_memory(p_buf, bytes_to_release);
2835 }
2836 #ifdef ASSERT
2837 if (should_inject_error) {
2838 log_develop_debug(pagesize)("Reserving pages individually failed.");
2839 }
2840 #endif
2841 return NULL;
2842 }
2843
2844 bytes_remaining -= bytes_to_rq;
2845 next_alloc_addr += bytes_to_rq;
2846 count++;
2847 }
2848 // Although the memory is allocated individually, it is returned as one.
2849 // NMT records it as one block.
2850 if ((flags & MEM_COMMIT) != 0) {
2851 MemTracker::record_virtual_memory_reserve_and_commit((address)p_buf, bytes, CALLER_PC);
2852 } else {
2853 MemTracker::record_virtual_memory_reserve((address)p_buf, bytes, CALLER_PC);
2854 }
2855
2856 // made it this far, success
2857 return p_buf;
2858 }
2859
2860
2861
2862 void os::large_page_init() {
2863 if (!UseLargePages) return;
2864
2865 // print a warning if any large page related flag is specified on command line
2866 bool warn_on_failure = !FLAG_IS_DEFAULT(UseLargePages) ||
2867 !FLAG_IS_DEFAULT(LargePageSizeInBytes);
2868 bool success = false;
2869
2870 #define WARN(msg) if (warn_on_failure) { warning(msg); }
2871 if (request_lock_memory_privilege()) {
2872 size_t s = GetLargePageMinimum();
2873 if (s) {
2874 #if defined(IA32) || defined(AMD64)
2875 if (s > 4*M || LargePageSizeInBytes > 4*M) {
2876 WARN("JVM cannot use large pages bigger than 4mb.");
2877 } else {
2878 #endif
2879 if (LargePageSizeInBytes && LargePageSizeInBytes % s == 0) {
2880 _large_page_size = LargePageSizeInBytes;
2881 } else {
2882 _large_page_size = s;
2883 }
2884 success = true;
2885 #if defined(IA32) || defined(AMD64)
2886 }
2887 #endif
2888 } else {
2889 WARN("Large page is not supported by the processor.");
2890 }
2891 } else {
2892 WARN("JVM cannot use large page memory because it does not have enough privilege to lock pages in memory.");
2893 }
2894 #undef WARN
2895
2896 const size_t default_page_size = (size_t) vm_page_size();
2897 if (success && _large_page_size > default_page_size) {
2898 _page_sizes[0] = _large_page_size;
2899 _page_sizes[1] = default_page_size;
2900 _page_sizes[2] = 0;
2901 }
2902
2903 cleanup_after_large_page_init();
2904 UseLargePages = success;
2905 }
2906
2907 // On win32, one cannot release just a part of reserved memory, it's an
2908 // all or nothing deal. When we split a reservation, we must break the
2909 // reservation into two reservations.
2910 void os::pd_split_reserved_memory(char *base, size_t size, size_t split,
2911 bool realloc) {
2912 if (size > 0) {
2913 release_memory(base, size);
2914 if (realloc) {
2915 reserve_memory(split, base);
2916 }
2917 if (size != split) {
2918 reserve_memory(size - split, base + split);
2919 }
2920 }
2921 }
2922
2923 // Multiple threads can race in this code but it's not possible to unmap small sections of
2924 // virtual space to get requested alignment, like posix-like os's.
2925 // Windows prevents multiple thread from remapping over each other so this loop is thread-safe.
2926 char* os::reserve_memory_aligned(size_t size, size_t alignment) {
2927 assert((alignment & (os::vm_allocation_granularity() - 1)) == 0,
2928 "Alignment must be a multiple of allocation granularity (page size)");
2929 assert((size & (alignment -1)) == 0, "size must be 'alignment' aligned");
2930
2931 size_t extra_size = size + alignment;
2932 assert(extra_size >= size, "overflow, size is too large to allow alignment");
2933
2934 char* aligned_base = NULL;
2935
2936 do {
2937 char* extra_base = os::reserve_memory(extra_size, NULL, alignment);
2938 if (extra_base == NULL) {
2939 return NULL;
2940 }
2941 // Do manual alignment
2942 aligned_base = align_up(extra_base, alignment);
2943
2944 os::release_memory(extra_base, extra_size);
2945
2946 aligned_base = os::reserve_memory(size, aligned_base);
2947
2948 } while (aligned_base == NULL);
2949
2950 return aligned_base;
2951 }
2952
2953 char* os::pd_reserve_memory(size_t bytes, char* addr, size_t alignment_hint) {
2954 assert((size_t)addr % os::vm_allocation_granularity() == 0,
2955 "reserve alignment");
2956 assert(bytes % os::vm_page_size() == 0, "reserve page size");
2957 char* res;
2958 // note that if UseLargePages is on, all the areas that require interleaving
2959 // will go thru reserve_memory_special rather than thru here.
2960 bool use_individual = (UseNUMAInterleaving && !UseLargePages);
2961 if (!use_individual) {
2962 res = (char*)VirtualAlloc(addr, bytes, MEM_RESERVE, PAGE_READWRITE);
2963 } else {
2964 elapsedTimer reserveTimer;
2965 if (Verbose && PrintMiscellaneous) reserveTimer.start();
2966 // in numa interleaving, we have to allocate pages individually
2967 // (well really chunks of NUMAInterleaveGranularity size)
2968 res = allocate_pages_individually(bytes, addr, MEM_RESERVE, PAGE_READWRITE);
2969 if (res == NULL) {
2970 warning("NUMA page allocation failed");
2971 }
2972 if (Verbose && PrintMiscellaneous) {
2973 reserveTimer.stop();
2974 tty->print_cr("reserve_memory of %Ix bytes took " JLONG_FORMAT " ms (" JLONG_FORMAT " ticks)", bytes,
2975 reserveTimer.milliseconds(), reserveTimer.ticks());
2976 }
2977 }
2978 assert(res == NULL || addr == NULL || addr == res,
2979 "Unexpected address from reserve.");
2980
2981 return res;
2982 }
2983
2984 // Reserve memory at an arbitrary address, only if that area is
2985 // available (and not reserved for something else).
2986 char* os::pd_attempt_reserve_memory_at(size_t bytes, char* requested_addr) {
2987 // Windows os::reserve_memory() fails of the requested address range is
2988 // not avilable.
2989 return reserve_memory(bytes, requested_addr);
2990 }
2991
2992 size_t os::large_page_size() {
2993 return _large_page_size;
2994 }
2995
2996 bool os::can_commit_large_page_memory() {
2997 // Windows only uses large page memory when the entire region is reserved
2998 // and committed in a single VirtualAlloc() call. This may change in the
2999 // future, but with Windows 2003 it's not possible to commit on demand.
3000 return false;
3001 }
3002
3003 bool os::can_execute_large_page_memory() {
3004 return true;
3005 }
3006
3007 char* os::reserve_memory_special(size_t bytes, size_t alignment, char* addr,
3008 bool exec) {
3009 assert(UseLargePages, "only for large pages");
3010
3011 if (!is_aligned(bytes, os::large_page_size()) || alignment > os::large_page_size()) {
3012 return NULL; // Fallback to small pages.
3013 }
3014
3015 const DWORD prot = exec ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
3016 const DWORD flags = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
3017
3018 // with large pages, there are two cases where we need to use Individual Allocation
3019 // 1) the UseLargePagesIndividualAllocation flag is set (set by default on WS2003)
3020 // 2) NUMA Interleaving is enabled, in which case we use a different node for each page
3021 if (UseLargePagesIndividualAllocation || UseNUMAInterleaving) {
3022 log_debug(pagesize)("Reserving large pages individually.");
3023
3024 char * p_buf = allocate_pages_individually(bytes, addr, flags, prot, LargePagesIndividualAllocationInjectError);
3025 if (p_buf == NULL) {
3026 // give an appropriate warning message
3027 if (UseNUMAInterleaving) {
3028 warning("NUMA large page allocation failed, UseLargePages flag ignored");
3029 }
3030 if (UseLargePagesIndividualAllocation) {
3031 warning("Individually allocated large pages failed, "
3032 "use -XX:-UseLargePagesIndividualAllocation to turn off");
3033 }
3034 return NULL;
3035 }
3036
3037 return p_buf;
3038
3039 } else {
3040 log_debug(pagesize)("Reserving large pages in a single large chunk.");
3041
3042 // normal policy just allocate it all at once
3043 DWORD flag = MEM_RESERVE | MEM_COMMIT | MEM_LARGE_PAGES;
3044 char * res = (char *)VirtualAlloc(addr, bytes, flag, prot);
3045 if (res != NULL) {
3046 MemTracker::record_virtual_memory_reserve_and_commit((address)res, bytes, CALLER_PC);
3047 }
3048
3049 return res;
3050 }
3051 }
3052
3053 bool os::release_memory_special(char* base, size_t bytes) {
3054 assert(base != NULL, "Sanity check");
3055 return release_memory(base, bytes);
3056 }
3057
3058 void os::print_statistics() {
3059 }
3060
3061 static void warn_fail_commit_memory(char* addr, size_t bytes, bool exec) {
3062 int err = os::get_last_error();
3063 char buf[256];
3064 size_t buf_len = os::lasterror(buf, sizeof(buf));
3065 warning("INFO: os::commit_memory(" PTR_FORMAT ", " SIZE_FORMAT
3066 ", %d) failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3067 exec, buf_len != 0 ? buf : "<no_error_string>", err);
3068 }
3069
3070 bool os::pd_commit_memory(char* addr, size_t bytes, bool exec) {
3071 if (bytes == 0) {
3072 // Don't bother the OS with noops.
3073 return true;
3074 }
3075 assert((size_t) addr % os::vm_page_size() == 0, "commit on page boundaries");
3076 assert(bytes % os::vm_page_size() == 0, "commit in page-sized chunks");
3077 // Don't attempt to print anything if the OS call fails. We're
3078 // probably low on resources, so the print itself may cause crashes.
3079
3080 // unless we have NUMAInterleaving enabled, the range of a commit
3081 // is always within a reserve covered by a single VirtualAlloc
3082 // in that case we can just do a single commit for the requested size
3083 if (!UseNUMAInterleaving) {
3084 if (VirtualAlloc(addr, bytes, MEM_COMMIT, PAGE_READWRITE) == NULL) {
3085 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3086 return false;
3087 }
3088 if (exec) {
3089 DWORD oldprot;
3090 // Windows doc says to use VirtualProtect to get execute permissions
3091 if (!VirtualProtect(addr, bytes, PAGE_EXECUTE_READWRITE, &oldprot)) {
3092 NOT_PRODUCT(warn_fail_commit_memory(addr, bytes, exec);)
3093 return false;
3094 }
3095 }
3096 return true;
3097 } else {
3098
3099 // when NUMAInterleaving is enabled, the commit might cover a range that
3100 // came from multiple VirtualAlloc reserves (using allocate_pages_individually).
3101 // VirtualQuery can help us determine that. The RegionSize that VirtualQuery
3102 // returns represents the number of bytes that can be committed in one step.
3103 size_t bytes_remaining = bytes;
3104 char * next_alloc_addr = addr;
3105 while (bytes_remaining > 0) {
3106 MEMORY_BASIC_INFORMATION alloc_info;
3107 VirtualQuery(next_alloc_addr, &alloc_info, sizeof(alloc_info));
3108 size_t bytes_to_rq = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3109 if (VirtualAlloc(next_alloc_addr, bytes_to_rq, MEM_COMMIT,
3110 PAGE_READWRITE) == NULL) {
3111 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3112 exec);)
3113 return false;
3114 }
3115 if (exec) {
3116 DWORD oldprot;
3117 if (!VirtualProtect(next_alloc_addr, bytes_to_rq,
3118 PAGE_EXECUTE_READWRITE, &oldprot)) {
3119 NOT_PRODUCT(warn_fail_commit_memory(next_alloc_addr, bytes_to_rq,
3120 exec);)
3121 return false;
3122 }
3123 }
3124 bytes_remaining -= bytes_to_rq;
3125 next_alloc_addr += bytes_to_rq;
3126 }
3127 }
3128 // if we made it this far, return true
3129 return true;
3130 }
3131
3132 bool os::pd_commit_memory(char* addr, size_t size, size_t alignment_hint,
3133 bool exec) {
3134 // alignment_hint is ignored on this OS
3135 return pd_commit_memory(addr, size, exec);
3136 }
3137
3138 void os::pd_commit_memory_or_exit(char* addr, size_t size, bool exec,
3139 const char* mesg) {
3140 assert(mesg != NULL, "mesg must be specified");
3141 if (!pd_commit_memory(addr, size, exec)) {
3142 warn_fail_commit_memory(addr, size, exec);
3143 vm_exit_out_of_memory(size, OOM_MMAP_ERROR, "%s", mesg);
3144 }
3145 }
3146
3147 void os::pd_commit_memory_or_exit(char* addr, size_t size,
3148 size_t alignment_hint, bool exec,
3149 const char* mesg) {
3150 // alignment_hint is ignored on this OS
3151 pd_commit_memory_or_exit(addr, size, exec, mesg);
3152 }
3153
3154 bool os::pd_uncommit_memory(char* addr, size_t bytes) {
3155 if (bytes == 0) {
3156 // Don't bother the OS with noops.
3157 return true;
3158 }
3159 assert((size_t) addr % os::vm_page_size() == 0, "uncommit on page boundaries");
3160 assert(bytes % os::vm_page_size() == 0, "uncommit in page-sized chunks");
3161 return (VirtualFree(addr, bytes, MEM_DECOMMIT) != 0);
3162 }
3163
3164 bool os::pd_release_memory(char* addr, size_t bytes) {
3165 return VirtualFree(addr, 0, MEM_RELEASE) != 0;
3166 }
3167
3168 bool os::pd_create_stack_guard_pages(char* addr, size_t size) {
3169 return os::commit_memory(addr, size, !ExecMem);
3170 }
3171
3172 bool os::remove_stack_guard_pages(char* addr, size_t size) {
3173 return os::uncommit_memory(addr, size);
3174 }
3175
3176 static bool protect_pages_individually(char* addr, size_t bytes, unsigned int p, DWORD *old_status) {
3177 uint count = 0;
3178 bool ret = false;
3179 size_t bytes_remaining = bytes;
3180 char * next_protect_addr = addr;
3181
3182 // Use VirtualQuery() to get the chunk size.
3183 while (bytes_remaining) {
3184 MEMORY_BASIC_INFORMATION alloc_info;
3185 if (VirtualQuery(next_protect_addr, &alloc_info, sizeof(alloc_info)) == 0) {
3186 return false;
3187 }
3188
3189 size_t bytes_to_protect = MIN2(bytes_remaining, (size_t)alloc_info.RegionSize);
3190 // We used different API at allocate_pages_individually() based on UseNUMAInterleaving,
3191 // but we don't distinguish here as both cases are protected by same API.
3192 ret = VirtualProtect(next_protect_addr, bytes_to_protect, p, old_status) != 0;
3193 warning("Failed protecting pages individually for chunk #%u", count);
3194 if (!ret) {
3195 return false;
3196 }
3197
3198 bytes_remaining -= bytes_to_protect;
3199 next_protect_addr += bytes_to_protect;
3200 count++;
3201 }
3202 return ret;
3203 }
3204
3205 // Set protections specified
3206 bool os::protect_memory(char* addr, size_t bytes, ProtType prot,
3207 bool is_committed) {
3208 unsigned int p = 0;
3209 switch (prot) {
3210 case MEM_PROT_NONE: p = PAGE_NOACCESS; break;
3211 case MEM_PROT_READ: p = PAGE_READONLY; break;
3212 case MEM_PROT_RW: p = PAGE_READWRITE; break;
3213 case MEM_PROT_RWX: p = PAGE_EXECUTE_READWRITE; break;
3214 default:
3215 ShouldNotReachHere();
3216 }
3217
3218 DWORD old_status;
3219
3220 // Strange enough, but on Win32 one can change protection only for committed
3221 // memory, not a big deal anyway, as bytes less or equal than 64K
3222 if (!is_committed) {
3223 commit_memory_or_exit(addr, bytes, prot == MEM_PROT_RWX,
3224 "cannot commit protection page");
3225 }
3226 // One cannot use os::guard_memory() here, as on Win32 guard page
3227 // have different (one-shot) semantics, from MSDN on PAGE_GUARD:
3228 //
3229 // Pages in the region become guard pages. Any attempt to access a guard page
3230 // causes the system to raise a STATUS_GUARD_PAGE exception and turn off
3231 // the guard page status. Guard pages thus act as a one-time access alarm.
3232 bool ret;
3233 if (UseNUMAInterleaving) {
3234 // If UseNUMAInterleaving is enabled, the pages may have been allocated a chunk at a time,
3235 // so we must protect the chunks individually.
3236 ret = protect_pages_individually(addr, bytes, p, &old_status);
3237 } else {
3238 ret = VirtualProtect(addr, bytes, p, &old_status) != 0;
3239 }
3240 #ifdef ASSERT
3241 if (!ret) {
3242 int err = os::get_last_error();
3243 char buf[256];
3244 size_t buf_len = os::lasterror(buf, sizeof(buf));
3245 warning("INFO: os::protect_memory(" PTR_FORMAT ", " SIZE_FORMAT
3246 ") failed; error='%s' (DOS error/errno=%d)", addr, bytes,
3247 buf_len != 0 ? buf : "<no_error_string>", err);
3248 }
3249 #endif
3250 return ret;
3251 }
3252
3253 bool os::guard_memory(char* addr, size_t bytes) {
3254 DWORD old_status;
3255 return VirtualProtect(addr, bytes, PAGE_READWRITE | PAGE_GUARD, &old_status) != 0;
3256 }
3257
3258 bool os::unguard_memory(char* addr, size_t bytes) {
3259 DWORD old_status;
3260 return VirtualProtect(addr, bytes, PAGE_READWRITE, &old_status) != 0;
3261 }
3262
3263 void os::pd_realign_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3264 void os::pd_free_memory(char *addr, size_t bytes, size_t alignment_hint) { }
3265 void os::numa_make_global(char *addr, size_t bytes) { }
3266 void os::numa_make_local(char *addr, size_t bytes, int lgrp_hint) { }
3267 bool os::numa_topology_changed() { return false; }
3268 size_t os::numa_get_groups_num() { return MAX2(numa_node_list_holder.get_count(), 1); }
3269 int os::numa_get_group_id() { return 0; }
3270 size_t os::numa_get_leaf_groups(int *ids, size_t size) {
3271 if (numa_node_list_holder.get_count() == 0 && size > 0) {
3272 // Provide an answer for UMA systems
3273 ids[0] = 0;
3274 return 1;
3275 } else {
3276 // check for size bigger than actual groups_num
3277 size = MIN2(size, numa_get_groups_num());
3278 for (int i = 0; i < (int)size; i++) {
3279 ids[i] = numa_node_list_holder.get_node_list_entry(i);
3280 }
3281 return size;
3282 }
3283 }
3284
3285 bool os::get_page_info(char *start, page_info* info) {
3286 return false;
3287 }
3288
3289 char *os::scan_pages(char *start, char* end, page_info* page_expected,
3290 page_info* page_found) {
3291 return end;
3292 }
3293
3294 char* os::non_memory_address_word() {
3295 // Must never look like an address returned by reserve_memory,
3296 // even in its subfields (as defined by the CPU immediate fields,
3297 // if the CPU splits constants across multiple instructions).
3298 return (char*)-1;
3299 }
3300
3301 #define MAX_ERROR_COUNT 100
3302 #define SYS_THREAD_ERROR 0xffffffffUL
3303
3304 void os::pd_start_thread(Thread* thread) {
3305 DWORD ret = ResumeThread(thread->osthread()->thread_handle());
3306 // Returns previous suspend state:
3307 // 0: Thread was not suspended
3308 // 1: Thread is running now
3309 // >1: Thread is still suspended.
3310 assert(ret != SYS_THREAD_ERROR, "StartThread failed"); // should propagate back
3311 }
3312
3313 class HighResolutionInterval : public CHeapObj<mtThread> {
3314 // The default timer resolution seems to be 10 milliseconds.
3315 // (Where is this written down?)
3316 // If someone wants to sleep for only a fraction of the default,
3317 // then we set the timer resolution down to 1 millisecond for
3318 // the duration of their interval.
3319 // We carefully set the resolution back, since otherwise we
3320 // seem to incur an overhead (3%?) that we don't need.
3321 // CONSIDER: if ms is small, say 3, then we should run with a high resolution time.
3322 // Buf if ms is large, say 500, or 503, we should avoid the call to timeBeginPeriod().
3323 // Alternatively, we could compute the relative error (503/500 = .6%) and only use
3324 // timeBeginPeriod() if the relative error exceeded some threshold.
3325 // timeBeginPeriod() has been linked to problems with clock drift on win32 systems and
3326 // to decreased efficiency related to increased timer "tick" rates. We want to minimize
3327 // (a) calls to timeBeginPeriod() and timeEndPeriod() and (b) time spent with high
3328 // resolution timers running.
3329 private:
3330 jlong resolution;
3331 public:
3332 HighResolutionInterval(jlong ms) {
3333 resolution = ms % 10L;
3334 if (resolution != 0) {
3335 MMRESULT result = timeBeginPeriod(1L);
3336 }
3337 }
3338 ~HighResolutionInterval() {
3339 if (resolution != 0) {
3340 MMRESULT result = timeEndPeriod(1L);
3341 }
3342 resolution = 0L;
3343 }
3344 };
3345
3346 int os::sleep(Thread* thread, jlong ms, bool interruptable) {
3347 jlong limit = (jlong) MAXDWORD;
3348
3349 while (ms > limit) {
3350 int res;
3351 if ((res = sleep(thread, limit, interruptable)) != OS_TIMEOUT) {
3352 return res;
3353 }
3354 ms -= limit;
3355 }
3356
3357 assert(thread == Thread::current(), "thread consistency check");
3358 OSThread* osthread = thread->osthread();
3359 OSThreadWaitState osts(osthread, false /* not Object.wait() */);
3360 int result;
3361 if (interruptable) {
3362 assert(thread->is_Java_thread(), "must be java thread");
3363 JavaThread *jt = (JavaThread *) thread;
3364 ThreadBlockInVM tbivm(jt);
3365
3366 jt->set_suspend_equivalent();
3367 // cleared by handle_special_suspend_equivalent_condition() or
3368 // java_suspend_self() via check_and_wait_while_suspended()
3369
3370 HANDLE events[1];
3371 events[0] = osthread->interrupt_event();
3372 HighResolutionInterval *phri=NULL;
3373 if (!ForceTimeHighResolution) {
3374 phri = new HighResolutionInterval(ms);
3375 }
3376 if (WaitForMultipleObjects(1, events, FALSE, (DWORD)ms) == WAIT_TIMEOUT) {
3377 result = OS_TIMEOUT;
3378 } else {
3379 ResetEvent(osthread->interrupt_event());
3380 osthread->set_interrupted(false);
3381 result = OS_INTRPT;
3382 }
3383 delete phri; //if it is NULL, harmless
3384
3385 // were we externally suspended while we were waiting?
3386 jt->check_and_wait_while_suspended();
3387 } else {
3388 assert(!thread->is_Java_thread(), "must not be java thread");
3389 Sleep((long) ms);
3390 result = OS_TIMEOUT;
3391 }
3392 return result;
3393 }
3394
3395 // Short sleep, direct OS call.
3396 //
3397 // ms = 0, means allow others (if any) to run.
3398 //
3399 void os::naked_short_sleep(jlong ms) {
3400 assert(ms < 1000, "Un-interruptable sleep, short time use only");
3401 Sleep(ms);
3402 }
3403
3404 // Sleep forever; naked call to OS-specific sleep; use with CAUTION
3405 void os::infinite_sleep() {
3406 while (true) { // sleep forever ...
3407 Sleep(100000); // ... 100 seconds at a time
3408 }
3409 }
3410
3411 typedef BOOL (WINAPI * STTSignature)(void);
3412
3413 void os::naked_yield() {
3414 // Consider passing back the return value from SwitchToThread().
3415 SwitchToThread();
3416 }
3417
3418 // Win32 only gives you access to seven real priorities at a time,
3419 // so we compress Java's ten down to seven. It would be better
3420 // if we dynamically adjusted relative priorities.
3421
3422 int os::java_to_os_priority[CriticalPriority + 1] = {
3423 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3424 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3425 THREAD_PRIORITY_LOWEST, // 2
3426 THREAD_PRIORITY_BELOW_NORMAL, // 3
3427 THREAD_PRIORITY_BELOW_NORMAL, // 4
3428 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3429 THREAD_PRIORITY_NORMAL, // 6
3430 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3431 THREAD_PRIORITY_ABOVE_NORMAL, // 8
3432 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3433 THREAD_PRIORITY_HIGHEST, // 10 MaxPriority
3434 THREAD_PRIORITY_HIGHEST // 11 CriticalPriority
3435 };
3436
3437 int prio_policy1[CriticalPriority + 1] = {
3438 THREAD_PRIORITY_IDLE, // 0 Entry should never be used
3439 THREAD_PRIORITY_LOWEST, // 1 MinPriority
3440 THREAD_PRIORITY_LOWEST, // 2
3441 THREAD_PRIORITY_BELOW_NORMAL, // 3
3442 THREAD_PRIORITY_BELOW_NORMAL, // 4
3443 THREAD_PRIORITY_NORMAL, // 5 NormPriority
3444 THREAD_PRIORITY_ABOVE_NORMAL, // 6
3445 THREAD_PRIORITY_ABOVE_NORMAL, // 7
3446 THREAD_PRIORITY_HIGHEST, // 8
3447 THREAD_PRIORITY_HIGHEST, // 9 NearMaxPriority
3448 THREAD_PRIORITY_TIME_CRITICAL, // 10 MaxPriority
3449 THREAD_PRIORITY_TIME_CRITICAL // 11 CriticalPriority
3450 };
3451
3452 static int prio_init() {
3453 // If ThreadPriorityPolicy is 1, switch tables
3454 if (ThreadPriorityPolicy == 1) {
3455 int i;
3456 for (i = 0; i < CriticalPriority + 1; i++) {
3457 os::java_to_os_priority[i] = prio_policy1[i];
3458 }
3459 }
3460 if (UseCriticalJavaThreadPriority) {
3461 os::java_to_os_priority[MaxPriority] = os::java_to_os_priority[CriticalPriority];
3462 }
3463 return 0;
3464 }
3465
3466 OSReturn os::set_native_priority(Thread* thread, int priority) {
3467 if (!UseThreadPriorities) return OS_OK;
3468 bool ret = SetThreadPriority(thread->osthread()->thread_handle(), priority) != 0;
3469 return ret ? OS_OK : OS_ERR;
3470 }
3471
3472 OSReturn os::get_native_priority(const Thread* const thread,
3473 int* priority_ptr) {
3474 if (!UseThreadPriorities) {
3475 *priority_ptr = java_to_os_priority[NormPriority];
3476 return OS_OK;
3477 }
3478 int os_prio = GetThreadPriority(thread->osthread()->thread_handle());
3479 if (os_prio == THREAD_PRIORITY_ERROR_RETURN) {
3480 assert(false, "GetThreadPriority failed");
3481 return OS_ERR;
3482 }
3483 *priority_ptr = os_prio;
3484 return OS_OK;
3485 }
3486
3487
3488 // Hint to the underlying OS that a task switch would not be good.
3489 // Void return because it's a hint and can fail.
3490 void os::hint_no_preempt() {}
3491
3492 void os::interrupt(Thread* thread) {
3493 assert(!thread->is_Java_thread() || Thread::current() == thread ||
3494 Threads_lock->owned_by_self(),
3495 "possibility of dangling Thread pointer");
3496
3497 OSThread* osthread = thread->osthread();
3498 osthread->set_interrupted(true);
3499 // More than one thread can get here with the same value of osthread,
3500 // resulting in multiple notifications. We do, however, want the store
3501 // to interrupted() to be visible to other threads before we post
3502 // the interrupt event.
3503 OrderAccess::release();
3504 SetEvent(osthread->interrupt_event());
3505 // For JSR166: unpark after setting status
3506 if (thread->is_Java_thread()) {
3507 ((JavaThread*)thread)->parker()->unpark();
3508 }
3509
3510 ParkEvent * ev = thread->_ParkEvent;
3511 if (ev != NULL) ev->unpark();
3512 }
3513
3514
3515 bool os::is_interrupted(Thread* thread, bool clear_interrupted) {
3516 assert(!thread->is_Java_thread() || Thread::current() == thread || Threads_lock->owned_by_self(),
3517 "possibility of dangling Thread pointer");
3518
3519 OSThread* osthread = thread->osthread();
3520 // There is no synchronization between the setting of the interrupt
3521 // and it being cleared here. It is critical - see 6535709 - that
3522 // we only clear the interrupt state, and reset the interrupt event,
3523 // if we are going to report that we were indeed interrupted - else
3524 // an interrupt can be "lost", leading to spurious wakeups or lost wakeups
3525 // depending on the timing. By checking thread interrupt event to see
3526 // if the thread gets real interrupt thus prevent spurious wakeup.
3527 bool interrupted = osthread->interrupted() && (WaitForSingleObject(osthread->interrupt_event(), 0) == WAIT_OBJECT_0);
3528 if (interrupted && clear_interrupted) {
3529 osthread->set_interrupted(false);
3530 ResetEvent(osthread->interrupt_event());
3531 } // Otherwise leave the interrupted state alone
3532
3533 return interrupted;
3534 }
3535
3536 // GetCurrentThreadId() returns DWORD
3537 intx os::current_thread_id() { return GetCurrentThreadId(); }
3538
3539 static int _initial_pid = 0;
3540
3541 int os::current_process_id() {
3542 return (_initial_pid ? _initial_pid : _getpid());
3543 }
3544
3545 int os::win32::_vm_page_size = 0;
3546 int os::win32::_vm_allocation_granularity = 0;
3547 int os::win32::_processor_type = 0;
3548 // Processor level is not available on non-NT systems, use vm_version instead
3549 int os::win32::_processor_level = 0;
3550 julong os::win32::_physical_memory = 0;
3551 size_t os::win32::_default_stack_size = 0;
3552
3553 intx os::win32::_os_thread_limit = 0;
3554 volatile intx os::win32::_os_thread_count = 0;
3555
3556 bool os::win32::_is_windows_server = false;
3557
3558 // 6573254
3559 // Currently, the bug is observed across all the supported Windows releases,
3560 // including the latest one (as of this writing - Windows Server 2012 R2)
3561 bool os::win32::_has_exit_bug = true;
3562
3563 void os::win32::initialize_system_info() {
3564 SYSTEM_INFO si;
3565 GetSystemInfo(&si);
3566 _vm_page_size = si.dwPageSize;
3567 _vm_allocation_granularity = si.dwAllocationGranularity;
3568 _processor_type = si.dwProcessorType;
3569 _processor_level = si.wProcessorLevel;
3570 set_processor_count(si.dwNumberOfProcessors);
3571
3572 MEMORYSTATUSEX ms;
3573 ms.dwLength = sizeof(ms);
3574
3575 // also returns dwAvailPhys (free physical memory bytes), dwTotalVirtual, dwAvailVirtual,
3576 // dwMemoryLoad (% of memory in use)
3577 GlobalMemoryStatusEx(&ms);
3578 _physical_memory = ms.ullTotalPhys;
3579
3580 if (FLAG_IS_DEFAULT(MaxRAM)) {
3581 // Adjust MaxRAM according to the maximum virtual address space available.
3582 FLAG_SET_DEFAULT(MaxRAM, MIN2(MaxRAM, (uint64_t) ms.ullTotalVirtual));
3583 }
3584
3585 OSVERSIONINFOEX oi;
3586 oi.dwOSVersionInfoSize = sizeof(OSVERSIONINFOEX);
3587 GetVersionEx((OSVERSIONINFO*)&oi);
3588 switch (oi.dwPlatformId) {
3589 case VER_PLATFORM_WIN32_NT:
3590 {
3591 int os_vers = oi.dwMajorVersion * 1000 + oi.dwMinorVersion;
3592 if (oi.wProductType == VER_NT_DOMAIN_CONTROLLER ||
3593 oi.wProductType == VER_NT_SERVER) {
3594 _is_windows_server = true;
3595 }
3596 }
3597 break;
3598 default: fatal("Unknown platform");
3599 }
3600
3601 _default_stack_size = os::current_stack_size();
3602 assert(_default_stack_size > (size_t) _vm_page_size, "invalid stack size");
3603 assert((_default_stack_size & (_vm_page_size - 1)) == 0,
3604 "stack size not a multiple of page size");
3605
3606 initialize_performance_counter();
3607 }
3608
3609
3610 HINSTANCE os::win32::load_Windows_dll(const char* name, char *ebuf,
3611 int ebuflen) {
3612 char path[MAX_PATH];
3613 DWORD size;
3614 DWORD pathLen = (DWORD)sizeof(path);
3615 HINSTANCE result = NULL;
3616
3617 // only allow library name without path component
3618 assert(strchr(name, '\\') == NULL, "path not allowed");
3619 assert(strchr(name, ':') == NULL, "path not allowed");
3620 if (strchr(name, '\\') != NULL || strchr(name, ':') != NULL) {
3621 jio_snprintf(ebuf, ebuflen,
3622 "Invalid parameter while calling os::win32::load_windows_dll(): cannot take path: %s", name);
3623 return NULL;
3624 }
3625
3626 // search system directory
3627 if ((size = GetSystemDirectory(path, pathLen)) > 0) {
3628 if (size >= pathLen) {
3629 return NULL; // truncated
3630 }
3631 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3632 return NULL; // truncated
3633 }
3634 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3635 return result;
3636 }
3637 }
3638
3639 // try Windows directory
3640 if ((size = GetWindowsDirectory(path, pathLen)) > 0) {
3641 if (size >= pathLen) {
3642 return NULL; // truncated
3643 }
3644 if (jio_snprintf(path + size, pathLen - size, "\\%s", name) == -1) {
3645 return NULL; // truncated
3646 }
3647 if ((result = (HINSTANCE)os::dll_load(path, ebuf, ebuflen)) != NULL) {
3648 return result;
3649 }
3650 }
3651
3652 jio_snprintf(ebuf, ebuflen,
3653 "os::win32::load_windows_dll() cannot load %s from system directories.", name);
3654 return NULL;
3655 }
3656
3657 #define MAXIMUM_THREADS_TO_KEEP (16 * MAXIMUM_WAIT_OBJECTS)
3658 #define EXIT_TIMEOUT 300000 /* 5 minutes */
3659
3660 static BOOL CALLBACK init_crit_sect_call(PINIT_ONCE, PVOID pcrit_sect, PVOID*) {
3661 InitializeCriticalSection((CRITICAL_SECTION*)pcrit_sect);
3662 return TRUE;
3663 }
3664
3665 int os::win32::exit_process_or_thread(Ept what, int exit_code) {
3666 // Basic approach:
3667 // - Each exiting thread registers its intent to exit and then does so.
3668 // - A thread trying to terminate the process must wait for all
3669 // threads currently exiting to complete their exit.
3670
3671 if (os::win32::has_exit_bug()) {
3672 // The array holds handles of the threads that have started exiting by calling
3673 // _endthreadex().
3674 // Should be large enough to avoid blocking the exiting thread due to lack of
3675 // a free slot.
3676 static HANDLE handles[MAXIMUM_THREADS_TO_KEEP];
3677 static int handle_count = 0;
3678
3679 static INIT_ONCE init_once_crit_sect = INIT_ONCE_STATIC_INIT;
3680 static CRITICAL_SECTION crit_sect;
3681 static volatile DWORD process_exiting = 0;
3682 int i, j;
3683 DWORD res;
3684 HANDLE hproc, hthr;
3685
3686 // We only attempt to register threads until a process exiting
3687 // thread manages to set the process_exiting flag. Any threads
3688 // that come through here after the process_exiting flag is set
3689 // are unregistered and will be caught in the SuspendThread()
3690 // infinite loop below.
3691 bool registered = false;
3692
3693 // The first thread that reached this point, initializes the critical section.
3694 if (!InitOnceExecuteOnce(&init_once_crit_sect, init_crit_sect_call, &crit_sect, NULL)) {
3695 warning("crit_sect initialization failed in %s: %d\n", __FILE__, __LINE__);
3696 } else if (OrderAccess::load_acquire(&process_exiting) == 0) {
3697 if (what != EPT_THREAD) {
3698 // Atomically set process_exiting before the critical section
3699 // to increase the visibility between racing threads.
3700 Atomic::cmpxchg(GetCurrentThreadId(), &process_exiting, (DWORD)0);
3701 }
3702 EnterCriticalSection(&crit_sect);
3703
3704 if (what == EPT_THREAD && OrderAccess::load_acquire(&process_exiting) == 0) {
3705 // Remove from the array those handles of the threads that have completed exiting.
3706 for (i = 0, j = 0; i < handle_count; ++i) {
3707 res = WaitForSingleObject(handles[i], 0 /* don't wait */);
3708 if (res == WAIT_TIMEOUT) {
3709 handles[j++] = handles[i];
3710 } else {
3711 if (res == WAIT_FAILED) {
3712 warning("WaitForSingleObject failed (%u) in %s: %d\n",
3713 GetLastError(), __FILE__, __LINE__);
3714 }
3715 // Don't keep the handle, if we failed waiting for it.
3716 CloseHandle(handles[i]);
3717 }
3718 }
3719
3720 // If there's no free slot in the array of the kept handles, we'll have to
3721 // wait until at least one thread completes exiting.
3722 if ((handle_count = j) == MAXIMUM_THREADS_TO_KEEP) {
3723 // Raise the priority of the oldest exiting thread to increase its chances
3724 // to complete sooner.
3725 SetThreadPriority(handles[0], THREAD_PRIORITY_ABOVE_NORMAL);
3726 res = WaitForMultipleObjects(MAXIMUM_WAIT_OBJECTS, handles, FALSE, EXIT_TIMEOUT);
3727 if (res >= WAIT_OBJECT_0 && res < (WAIT_OBJECT_0 + MAXIMUM_WAIT_OBJECTS)) {
3728 i = (res - WAIT_OBJECT_0);
3729 handle_count = MAXIMUM_THREADS_TO_KEEP - 1;
3730 for (; i < handle_count; ++i) {
3731 handles[i] = handles[i + 1];
3732 }
3733 } else {
3734 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3735 (res == WAIT_FAILED ? "failed" : "timed out"),
3736 GetLastError(), __FILE__, __LINE__);
3737 // Don't keep handles, if we failed waiting for them.
3738 for (i = 0; i < MAXIMUM_THREADS_TO_KEEP; ++i) {
3739 CloseHandle(handles[i]);
3740 }
3741 handle_count = 0;
3742 }
3743 }
3744
3745 // Store a duplicate of the current thread handle in the array of handles.
3746 hproc = GetCurrentProcess();
3747 hthr = GetCurrentThread();
3748 if (!DuplicateHandle(hproc, hthr, hproc, &handles[handle_count],
3749 0, FALSE, DUPLICATE_SAME_ACCESS)) {
3750 warning("DuplicateHandle failed (%u) in %s: %d\n",
3751 GetLastError(), __FILE__, __LINE__);
3752
3753 // We can't register this thread (no more handles) so this thread
3754 // may be racing with a thread that is calling exit(). If the thread
3755 // that is calling exit() has managed to set the process_exiting
3756 // flag, then this thread will be caught in the SuspendThread()
3757 // infinite loop below which closes that race. A small timing
3758 // window remains before the process_exiting flag is set, but it
3759 // is only exposed when we are out of handles.
3760 } else {
3761 ++handle_count;
3762 registered = true;
3763
3764 // The current exiting thread has stored its handle in the array, and now
3765 // should leave the critical section before calling _endthreadex().
3766 }
3767
3768 } else if (what != EPT_THREAD && handle_count > 0) {
3769 jlong start_time, finish_time, timeout_left;
3770 // Before ending the process, make sure all the threads that had called
3771 // _endthreadex() completed.
3772
3773 // Set the priority level of the current thread to the same value as
3774 // the priority level of exiting threads.
3775 // This is to ensure it will be given a fair chance to execute if
3776 // the timeout expires.
3777 hthr = GetCurrentThread();
3778 SetThreadPriority(hthr, THREAD_PRIORITY_ABOVE_NORMAL);
3779 start_time = os::javaTimeNanos();
3780 finish_time = start_time + ((jlong)EXIT_TIMEOUT * 1000000L);
3781 for (i = 0; ; ) {
3782 int portion_count = handle_count - i;
3783 if (portion_count > MAXIMUM_WAIT_OBJECTS) {
3784 portion_count = MAXIMUM_WAIT_OBJECTS;
3785 }
3786 for (j = 0; j < portion_count; ++j) {
3787 SetThreadPriority(handles[i + j], THREAD_PRIORITY_ABOVE_NORMAL);
3788 }
3789 timeout_left = (finish_time - start_time) / 1000000L;
3790 if (timeout_left < 0) {
3791 timeout_left = 0;
3792 }
3793 res = WaitForMultipleObjects(portion_count, handles + i, TRUE, timeout_left);
3794 if (res == WAIT_FAILED || res == WAIT_TIMEOUT) {
3795 warning("WaitForMultipleObjects %s (%u) in %s: %d\n",
3796 (res == WAIT_FAILED ? "failed" : "timed out"),
3797 GetLastError(), __FILE__, __LINE__);
3798 // Reset portion_count so we close the remaining
3799 // handles due to this error.
3800 portion_count = handle_count - i;
3801 }
3802 for (j = 0; j < portion_count; ++j) {
3803 CloseHandle(handles[i + j]);
3804 }
3805 if ((i += portion_count) >= handle_count) {
3806 break;
3807 }
3808 start_time = os::javaTimeNanos();
3809 }
3810 handle_count = 0;
3811 }
3812
3813 LeaveCriticalSection(&crit_sect);
3814 }
3815
3816 if (!registered &&
3817 OrderAccess::load_acquire(&process_exiting) != 0 &&
3818 process_exiting != GetCurrentThreadId()) {
3819 // Some other thread is about to call exit(), so we don't let
3820 // the current unregistered thread proceed to exit() or _endthreadex()
3821 while (true) {
3822 SuspendThread(GetCurrentThread());
3823 // Avoid busy-wait loop, if SuspendThread() failed.
3824 Sleep(EXIT_TIMEOUT);
3825 }
3826 }
3827 }
3828
3829 // We are here if either
3830 // - there's no 'race at exit' bug on this OS release;
3831 // - initialization of the critical section failed (unlikely);
3832 // - the current thread has registered itself and left the critical section;
3833 // - the process-exiting thread has raised the flag and left the critical section.
3834 if (what == EPT_THREAD) {
3835 _endthreadex((unsigned)exit_code);
3836 } else if (what == EPT_PROCESS) {
3837 ::exit(exit_code);
3838 } else {
3839 _exit(exit_code);
3840 }
3841
3842 // Should not reach here
3843 return exit_code;
3844 }
3845
3846 #undef EXIT_TIMEOUT
3847
3848 void os::win32::setmode_streams() {
3849 _setmode(_fileno(stdin), _O_BINARY);
3850 _setmode(_fileno(stdout), _O_BINARY);
3851 _setmode(_fileno(stderr), _O_BINARY);
3852 }
3853
3854
3855 bool os::is_debugger_attached() {
3856 return IsDebuggerPresent() ? true : false;
3857 }
3858
3859
3860 void os::wait_for_keypress_at_exit(void) {
3861 if (PauseAtExit) {
3862 fprintf(stderr, "Press any key to continue...\n");
3863 fgetc(stdin);
3864 }
3865 }
3866
3867
3868 bool os::message_box(const char* title, const char* message) {
3869 int result = MessageBox(NULL, message, title,
3870 MB_YESNO | MB_ICONERROR | MB_SYSTEMMODAL | MB_DEFAULT_DESKTOP_ONLY);
3871 return result == IDYES;
3872 }
3873
3874 #ifndef PRODUCT
3875 #ifndef _WIN64
3876 // Helpers to check whether NX protection is enabled
3877 int nx_exception_filter(_EXCEPTION_POINTERS *pex) {
3878 if (pex->ExceptionRecord->ExceptionCode == EXCEPTION_ACCESS_VIOLATION &&
3879 pex->ExceptionRecord->NumberParameters > 0 &&
3880 pex->ExceptionRecord->ExceptionInformation[0] ==
3881 EXCEPTION_INFO_EXEC_VIOLATION) {
3882 return EXCEPTION_EXECUTE_HANDLER;
3883 }
3884 return EXCEPTION_CONTINUE_SEARCH;
3885 }
3886
3887 void nx_check_protection() {
3888 // If NX is enabled we'll get an exception calling into code on the stack
3889 char code[] = { (char)0xC3 }; // ret
3890 void *code_ptr = (void *)code;
3891 __try {
3892 __asm call code_ptr
3893 } __except(nx_exception_filter((_EXCEPTION_POINTERS*)_exception_info())) {
3894 tty->print_raw_cr("NX protection detected.");
3895 }
3896 }
3897 #endif // _WIN64
3898 #endif // PRODUCT
3899
3900 // This is called _before_ the global arguments have been parsed
3901 void os::init(void) {
3902 _initial_pid = _getpid();
3903
3904 init_random(1234567);
3905
3906 win32::initialize_system_info();
3907 win32::setmode_streams();
3908 init_page_sizes((size_t) win32::vm_page_size());
3909
3910 // This may be overridden later when argument processing is done.
3911 FLAG_SET_ERGO(bool, UseLargePagesIndividualAllocation, false);
3912
3913 // Initialize main_process and main_thread
3914 main_process = GetCurrentProcess(); // Remember main_process is a pseudo handle
3915 if (!DuplicateHandle(main_process, GetCurrentThread(), main_process,
3916 &main_thread, THREAD_ALL_ACCESS, false, 0)) {
3917 fatal("DuplicateHandle failed\n");
3918 }
3919 main_thread_id = (int) GetCurrentThreadId();
3920
3921 // initialize fast thread access - only used for 32-bit
3922 win32::initialize_thread_ptr_offset();
3923 }
3924
3925 // To install functions for atexit processing
3926 extern "C" {
3927 static void perfMemory_exit_helper() {
3928 perfMemory_exit();
3929 }
3930 }
3931
3932 static jint initSock();
3933
3934 // this is called _after_ the global arguments have been parsed
3935 jint os::init_2(void) {
3936 // Setup Windows Exceptions
3937
3938 // for debugging float code generation bugs
3939 if (ForceFloatExceptions) {
3940 #ifndef _WIN64
3941 static long fp_control_word = 0;
3942 __asm { fstcw fp_control_word }
3943 // see Intel PPro Manual, Vol. 2, p 7-16
3944 const long precision = 0x20;
3945 const long underflow = 0x10;
3946 const long overflow = 0x08;
3947 const long zero_div = 0x04;
3948 const long denorm = 0x02;
3949 const long invalid = 0x01;
3950 fp_control_word |= invalid;
3951 __asm { fldcw fp_control_word }
3952 #endif
3953 }
3954
3955 // If stack_commit_size is 0, windows will reserve the default size,
3956 // but only commit a small portion of it.
3957 size_t stack_commit_size = align_up(ThreadStackSize*K, os::vm_page_size());
3958 size_t default_reserve_size = os::win32::default_stack_size();
3959 size_t actual_reserve_size = stack_commit_size;
3960 if (stack_commit_size < default_reserve_size) {
3961 // If stack_commit_size == 0, we want this too
3962 actual_reserve_size = default_reserve_size;
3963 }
3964
3965 // Check minimum allowable stack size for thread creation and to initialize
3966 // the java system classes, including StackOverflowError - depends on page
3967 // size. Add two 4K pages for compiler2 recursion in main thread.
3968 // Add in 4*BytesPerWord 4K pages to account for VM stack during
3969 // class initialization depending on 32 or 64 bit VM.
3970 size_t min_stack_allowed =
3971 (size_t)(JavaThread::stack_guard_zone_size() +
3972 JavaThread::stack_shadow_zone_size() +
3973 (4*BytesPerWord COMPILER2_PRESENT(+2)) * 4 * K);
3974
3975 min_stack_allowed = align_up(min_stack_allowed, os::vm_page_size());
3976
3977 if (actual_reserve_size < min_stack_allowed) {
3978 tty->print_cr("\nThe Java thread stack size specified is too small. "
3979 "Specify at least %dk",
3980 min_stack_allowed / K);
3981 return JNI_ERR;
3982 }
3983
3984 JavaThread::set_stack_size_at_create(stack_commit_size);
3985
3986 // Calculate theoretical max. size of Threads to guard gainst artifical
3987 // out-of-memory situations, where all available address-space has been
3988 // reserved by thread stacks.
3989 assert(actual_reserve_size != 0, "Must have a stack");
3990
3991 // Calculate the thread limit when we should start doing Virtual Memory
3992 // banging. Currently when the threads will have used all but 200Mb of space.
3993 //
3994 // TODO: consider performing a similar calculation for commit size instead
3995 // as reserve size, since on a 64-bit platform we'll run into that more
3996 // often than running out of virtual memory space. We can use the
3997 // lower value of the two calculations as the os_thread_limit.
3998 size_t max_address_space = ((size_t)1 << (BitsPerWord - 1)) - (200 * K * K);
3999 win32::_os_thread_limit = (intx)(max_address_space / actual_reserve_size);
4000
4001 // at exit methods are called in the reverse order of their registration.
4002 // there is no limit to the number of functions registered. atexit does
4003 // not set errno.
4004
4005 if (PerfAllowAtExitRegistration) {
4006 // only register atexit functions if PerfAllowAtExitRegistration is set.
4007 // atexit functions can be delayed until process exit time, which
4008 // can be problematic for embedded VM situations. Embedded VMs should
4009 // call DestroyJavaVM() to assure that VM resources are released.
4010
4011 // note: perfMemory_exit_helper atexit function may be removed in
4012 // the future if the appropriate cleanup code can be added to the
4013 // VM_Exit VMOperation's doit method.
4014 if (atexit(perfMemory_exit_helper) != 0) {
4015 warning("os::init_2 atexit(perfMemory_exit_helper) failed");
4016 }
4017 }
4018
4019 #ifndef _WIN64
4020 // Print something if NX is enabled (win32 on AMD64)
4021 NOT_PRODUCT(if (PrintMiscellaneous && Verbose) nx_check_protection());
4022 #endif
4023
4024 // initialize thread priority policy
4025 prio_init();
4026
4027 if (UseNUMA && !ForceNUMA) {
4028 UseNUMA = false; // We don't fully support this yet
4029 }
4030
4031 if (UseNUMAInterleaving) {
4032 // first check whether this Windows OS supports VirtualAllocExNuma, if not ignore this flag
4033 bool success = numa_interleaving_init();
4034 if (!success) UseNUMAInterleaving = false;
4035 }
4036
4037 if (initSock() != JNI_OK) {
4038 return JNI_ERR;
4039 }
4040
4041 SymbolEngine::recalc_search_path();
4042
4043 return JNI_OK;
4044 }
4045
4046 // Mark the polling page as unreadable
4047 void os::make_polling_page_unreadable(void) {
4048 DWORD old_status;
4049 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4050 PAGE_NOACCESS, &old_status)) {
4051 fatal("Could not disable polling page");
4052 }
4053 }
4054
4055 // Mark the polling page as readable
4056 void os::make_polling_page_readable(void) {
4057 DWORD old_status;
4058 if (!VirtualProtect((char *)_polling_page, os::vm_page_size(),
4059 PAGE_READONLY, &old_status)) {
4060 fatal("Could not enable polling page");
4061 }
4062 }
4063
4064
4065 int os::stat(const char *path, struct stat *sbuf) {
4066 char pathbuf[MAX_PATH];
4067 if (strlen(path) > MAX_PATH - 1) {
4068 errno = ENAMETOOLONG;
4069 return -1;
4070 }
4071 os::native_path(strcpy(pathbuf, path));
4072 int ret = ::stat(pathbuf, sbuf);
4073 if (sbuf != NULL && UseUTCFileTimestamp) {
4074 // Fix for 6539723. st_mtime returned from stat() is dependent on
4075 // the system timezone and so can return different values for the
4076 // same file if/when daylight savings time changes. This adjustment
4077 // makes sure the same timestamp is returned regardless of the TZ.
4078 //
4079 // See:
4080 // http://msdn.microsoft.com/library/
4081 // default.asp?url=/library/en-us/sysinfo/base/
4082 // time_zone_information_str.asp
4083 // and
4084 // http://msdn.microsoft.com/library/default.asp?url=
4085 // /library/en-us/sysinfo/base/settimezoneinformation.asp
4086 //
4087 // NOTE: there is a insidious bug here: If the timezone is changed
4088 // after the call to stat() but before 'GetTimeZoneInformation()', then
4089 // the adjustment we do here will be wrong and we'll return the wrong
4090 // value (which will likely end up creating an invalid class data
4091 // archive). Absent a better API for this, or some time zone locking
4092 // mechanism, we'll have to live with this risk.
4093 TIME_ZONE_INFORMATION tz;
4094 DWORD tzid = GetTimeZoneInformation(&tz);
4095 int daylightBias =
4096 (tzid == TIME_ZONE_ID_DAYLIGHT) ? tz.DaylightBias : tz.StandardBias;
4097 sbuf->st_mtime += (tz.Bias + daylightBias) * 60;
4098 }
4099 return ret;
4100 }
4101
4102
4103 #define FT2INT64(ft) \
4104 ((jlong)((jlong)(ft).dwHighDateTime << 32 | (julong)(ft).dwLowDateTime))
4105
4106
4107 // current_thread_cpu_time(bool) and thread_cpu_time(Thread*, bool)
4108 // are used by JVM M&M and JVMTI to get user+sys or user CPU time
4109 // of a thread.
4110 //
4111 // current_thread_cpu_time() and thread_cpu_time(Thread*) returns
4112 // the fast estimate available on the platform.
4113
4114 // current_thread_cpu_time() is not optimized for Windows yet
4115 jlong os::current_thread_cpu_time() {
4116 // return user + sys since the cost is the same
4117 return os::thread_cpu_time(Thread::current(), true /* user+sys */);
4118 }
4119
4120 jlong os::thread_cpu_time(Thread* thread) {
4121 // consistent with what current_thread_cpu_time() returns.
4122 return os::thread_cpu_time(thread, true /* user+sys */);
4123 }
4124
4125 jlong os::current_thread_cpu_time(bool user_sys_cpu_time) {
4126 return os::thread_cpu_time(Thread::current(), user_sys_cpu_time);
4127 }
4128
4129 jlong os::thread_cpu_time(Thread* thread, bool user_sys_cpu_time) {
4130 // This code is copy from clasic VM -> hpi::sysThreadCPUTime
4131 // If this function changes, os::is_thread_cpu_time_supported() should too
4132 FILETIME CreationTime;
4133 FILETIME ExitTime;
4134 FILETIME KernelTime;
4135 FILETIME UserTime;
4136
4137 if (GetThreadTimes(thread->osthread()->thread_handle(), &CreationTime,
4138 &ExitTime, &KernelTime, &UserTime) == 0) {
4139 return -1;
4140 } else if (user_sys_cpu_time) {
4141 return (FT2INT64(UserTime) + FT2INT64(KernelTime)) * 100;
4142 } else {
4143 return FT2INT64(UserTime) * 100;
4144 }
4145 }
4146
4147 void os::current_thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4148 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4149 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4150 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4151 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4152 }
4153
4154 void os::thread_cpu_time_info(jvmtiTimerInfo *info_ptr) {
4155 info_ptr->max_value = ALL_64_BITS; // the max value -- all 64 bits
4156 info_ptr->may_skip_backward = false; // GetThreadTimes returns absolute time
4157 info_ptr->may_skip_forward = false; // GetThreadTimes returns absolute time
4158 info_ptr->kind = JVMTI_TIMER_TOTAL_CPU; // user+system time is returned
4159 }
4160
4161 bool os::is_thread_cpu_time_supported() {
4162 // see os::thread_cpu_time
4163 FILETIME CreationTime;
4164 FILETIME ExitTime;
4165 FILETIME KernelTime;
4166 FILETIME UserTime;
4167
4168 if (GetThreadTimes(GetCurrentThread(), &CreationTime, &ExitTime,
4169 &KernelTime, &UserTime) == 0) {
4170 return false;
4171 } else {
4172 return true;
4173 }
4174 }
4175
4176 // Windows does't provide a loadavg primitive so this is stubbed out for now.
4177 // It does have primitives (PDH API) to get CPU usage and run queue length.
4178 // "\\Processor(_Total)\\% Processor Time", "\\System\\Processor Queue Length"
4179 // If we wanted to implement loadavg on Windows, we have a few options:
4180 //
4181 // a) Query CPU usage and run queue length and "fake" an answer by
4182 // returning the CPU usage if it's under 100%, and the run queue
4183 // length otherwise. It turns out that querying is pretty slow
4184 // on Windows, on the order of 200 microseconds on a fast machine.
4185 // Note that on the Windows the CPU usage value is the % usage
4186 // since the last time the API was called (and the first call
4187 // returns 100%), so we'd have to deal with that as well.
4188 //
4189 // b) Sample the "fake" answer using a sampling thread and store
4190 // the answer in a global variable. The call to loadavg would
4191 // just return the value of the global, avoiding the slow query.
4192 //
4193 // c) Sample a better answer using exponential decay to smooth the
4194 // value. This is basically the algorithm used by UNIX kernels.
4195 //
4196 // Note that sampling thread starvation could affect both (b) and (c).
4197 int os::loadavg(double loadavg[], int nelem) {
4198 return -1;
4199 }
4200
4201
4202 // DontYieldALot=false by default: dutifully perform all yields as requested by JVM_Yield()
4203 bool os::dont_yield() {
4204 return DontYieldALot;
4205 }
4206
4207 // This method is a slightly reworked copy of JDK's sysOpen
4208 // from src/windows/hpi/src/sys_api_md.c
4209
4210 int os::open(const char *path, int oflag, int mode) {
4211 char pathbuf[MAX_PATH];
4212
4213 if (strlen(path) > MAX_PATH - 1) {
4214 errno = ENAMETOOLONG;
4215 return -1;
4216 }
4217 os::native_path(strcpy(pathbuf, path));
4218 return ::open(pathbuf, oflag | O_BINARY | O_NOINHERIT, mode);
4219 }
4220
4221 FILE* os::open(int fd, const char* mode) {
4222 return ::_fdopen(fd, mode);
4223 }
4224
4225 // Is a (classpath) directory empty?
4226 bool os::dir_is_empty(const char* path) {
4227 WIN32_FIND_DATA fd;
4228 HANDLE f = FindFirstFile(path, &fd);
4229 if (f == INVALID_HANDLE_VALUE) {
4230 return true;
4231 }
4232 FindClose(f);
4233 return false;
4234 }
4235
4236 // create binary file, rewriting existing file if required
4237 int os::create_binary_file(const char* path, bool rewrite_existing) {
4238 int oflags = _O_CREAT | _O_WRONLY | _O_BINARY;
4239 if (!rewrite_existing) {
4240 oflags |= _O_EXCL;
4241 }
4242 return ::open(path, oflags, _S_IREAD | _S_IWRITE);
4243 }
4244
4245 // return current position of file pointer
4246 jlong os::current_file_offset(int fd) {
4247 return (jlong)::_lseeki64(fd, (__int64)0L, SEEK_CUR);
4248 }
4249
4250 // move file pointer to the specified offset
4251 jlong os::seek_to_file_offset(int fd, jlong offset) {
4252 return (jlong)::_lseeki64(fd, (__int64)offset, SEEK_SET);
4253 }
4254
4255
4256 jlong os::lseek(int fd, jlong offset, int whence) {
4257 return (jlong) ::_lseeki64(fd, offset, whence);
4258 }
4259
4260 size_t os::read_at(int fd, void *buf, unsigned int nBytes, jlong offset) {
4261 OVERLAPPED ov;
4262 DWORD nread;
4263 BOOL result;
4264
4265 ZeroMemory(&ov, sizeof(ov));
4266 ov.Offset = (DWORD)offset;
4267 ov.OffsetHigh = (DWORD)(offset >> 32);
4268
4269 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4270
4271 result = ReadFile(h, (LPVOID)buf, nBytes, &nread, &ov);
4272
4273 return result ? nread : 0;
4274 }
4275
4276
4277 // This method is a slightly reworked copy of JDK's sysNativePath
4278 // from src/windows/hpi/src/path_md.c
4279
4280 // Convert a pathname to native format. On win32, this involves forcing all
4281 // separators to be '\\' rather than '/' (both are legal inputs, but Win95
4282 // sometimes rejects '/') and removing redundant separators. The input path is
4283 // assumed to have been converted into the character encoding used by the local
4284 // system. Because this might be a double-byte encoding, care is taken to
4285 // treat double-byte lead characters correctly.
4286 //
4287 // This procedure modifies the given path in place, as the result is never
4288 // longer than the original. There is no error return; this operation always
4289 // succeeds.
4290 char * os::native_path(char *path) {
4291 char *src = path, *dst = path, *end = path;
4292 char *colon = NULL; // If a drive specifier is found, this will
4293 // point to the colon following the drive letter
4294
4295 // Assumption: '/', '\\', ':', and drive letters are never lead bytes
4296 assert(((!::IsDBCSLeadByte('/')) && (!::IsDBCSLeadByte('\\'))
4297 && (!::IsDBCSLeadByte(':'))), "Illegal lead byte");
4298
4299 // Check for leading separators
4300 #define isfilesep(c) ((c) == '/' || (c) == '\\')
4301 while (isfilesep(*src)) {
4302 src++;
4303 }
4304
4305 if (::isalpha(*src) && !::IsDBCSLeadByte(*src) && src[1] == ':') {
4306 // Remove leading separators if followed by drive specifier. This
4307 // hack is necessary to support file URLs containing drive
4308 // specifiers (e.g., "file://c:/path"). As a side effect,
4309 // "/c:/path" can be used as an alternative to "c:/path".
4310 *dst++ = *src++;
4311 colon = dst;
4312 *dst++ = ':';
4313 src++;
4314 } else {
4315 src = path;
4316 if (isfilesep(src[0]) && isfilesep(src[1])) {
4317 // UNC pathname: Retain first separator; leave src pointed at
4318 // second separator so that further separators will be collapsed
4319 // into the second separator. The result will be a pathname
4320 // beginning with "\\\\" followed (most likely) by a host name.
4321 src = dst = path + 1;
4322 path[0] = '\\'; // Force first separator to '\\'
4323 }
4324 }
4325
4326 end = dst;
4327
4328 // Remove redundant separators from remainder of path, forcing all
4329 // separators to be '\\' rather than '/'. Also, single byte space
4330 // characters are removed from the end of the path because those
4331 // are not legal ending characters on this operating system.
4332 //
4333 while (*src != '\0') {
4334 if (isfilesep(*src)) {
4335 *dst++ = '\\'; src++;
4336 while (isfilesep(*src)) src++;
4337 if (*src == '\0') {
4338 // Check for trailing separator
4339 end = dst;
4340 if (colon == dst - 2) break; // "z:\\"
4341 if (dst == path + 1) break; // "\\"
4342 if (dst == path + 2 && isfilesep(path[0])) {
4343 // "\\\\" is not collapsed to "\\" because "\\\\" marks the
4344 // beginning of a UNC pathname. Even though it is not, by
4345 // itself, a valid UNC pathname, we leave it as is in order
4346 // to be consistent with the path canonicalizer as well
4347 // as the win32 APIs, which treat this case as an invalid
4348 // UNC pathname rather than as an alias for the root
4349 // directory of the current drive.
4350 break;
4351 }
4352 end = --dst; // Path does not denote a root directory, so
4353 // remove trailing separator
4354 break;
4355 }
4356 end = dst;
4357 } else {
4358 if (::IsDBCSLeadByte(*src)) { // Copy a double-byte character
4359 *dst++ = *src++;
4360 if (*src) *dst++ = *src++;
4361 end = dst;
4362 } else { // Copy a single-byte character
4363 char c = *src++;
4364 *dst++ = c;
4365 // Space is not a legal ending character
4366 if (c != ' ') end = dst;
4367 }
4368 }
4369 }
4370
4371 *end = '\0';
4372
4373 // For "z:", add "." to work around a bug in the C runtime library
4374 if (colon == dst - 1) {
4375 path[2] = '.';
4376 path[3] = '\0';
4377 }
4378
4379 return path;
4380 }
4381
4382 // This code is a copy of JDK's sysSetLength
4383 // from src/windows/hpi/src/sys_api_md.c
4384
4385 int os::ftruncate(int fd, jlong length) {
4386 HANDLE h = (HANDLE)::_get_osfhandle(fd);
4387 long high = (long)(length >> 32);
4388 DWORD ret;
4389
4390 if (h == (HANDLE)(-1)) {
4391 return -1;
4392 }
4393
4394 ret = ::SetFilePointer(h, (long)(length), &high, FILE_BEGIN);
4395 if ((ret == 0xFFFFFFFF) && (::GetLastError() != NO_ERROR)) {
4396 return -1;
4397 }
4398
4399 if (::SetEndOfFile(h) == FALSE) {
4400 return -1;
4401 }
4402
4403 return 0;
4404 }
4405
4406 int os::get_fileno(FILE* fp) {
4407 return _fileno(fp);
4408 }
4409
4410 // This code is a copy of JDK's sysSync
4411 // from src/windows/hpi/src/sys_api_md.c
4412 // except for the legacy workaround for a bug in Win 98
4413
4414 int os::fsync(int fd) {
4415 HANDLE handle = (HANDLE)::_get_osfhandle(fd);
4416
4417 if ((!::FlushFileBuffers(handle)) &&
4418 (GetLastError() != ERROR_ACCESS_DENIED)) {
4419 // from winerror.h
4420 return -1;
4421 }
4422 return 0;
4423 }
4424
4425 static int nonSeekAvailable(int, long *);
4426 static int stdinAvailable(int, long *);
4427
4428 #define S_ISCHR(mode) (((mode) & _S_IFCHR) == _S_IFCHR)
4429 #define S_ISFIFO(mode) (((mode) & _S_IFIFO) == _S_IFIFO)
4430
4431 // This code is a copy of JDK's sysAvailable
4432 // from src/windows/hpi/src/sys_api_md.c
4433
4434 int os::available(int fd, jlong *bytes) {
4435 jlong cur, end;
4436 struct _stati64 stbuf64;
4437
4438 if (::_fstati64(fd, &stbuf64) >= 0) {
4439 int mode = stbuf64.st_mode;
4440 if (S_ISCHR(mode) || S_ISFIFO(mode)) {
4441 int ret;
4442 long lpbytes;
4443 if (fd == 0) {
4444 ret = stdinAvailable(fd, &lpbytes);
4445 } else {
4446 ret = nonSeekAvailable(fd, &lpbytes);
4447 }
4448 (*bytes) = (jlong)(lpbytes);
4449 return ret;
4450 }
4451 if ((cur = ::_lseeki64(fd, 0L, SEEK_CUR)) == -1) {
4452 return FALSE;
4453 } else if ((end = ::_lseeki64(fd, 0L, SEEK_END)) == -1) {
4454 return FALSE;
4455 } else if (::_lseeki64(fd, cur, SEEK_SET) == -1) {
4456 return FALSE;
4457 }
4458 *bytes = end - cur;
4459 return TRUE;
4460 } else {
4461 return FALSE;
4462 }
4463 }
4464
4465 void os::flockfile(FILE* fp) {
4466 _lock_file(fp);
4467 }
4468
4469 void os::funlockfile(FILE* fp) {
4470 _unlock_file(fp);
4471 }
4472
4473 // This code is a copy of JDK's nonSeekAvailable
4474 // from src/windows/hpi/src/sys_api_md.c
4475
4476 static int nonSeekAvailable(int fd, long *pbytes) {
4477 // This is used for available on non-seekable devices
4478 // (like both named and anonymous pipes, such as pipes
4479 // connected to an exec'd process).
4480 // Standard Input is a special case.
4481 HANDLE han;
4482
4483 if ((han = (HANDLE) ::_get_osfhandle(fd)) == (HANDLE)(-1)) {
4484 return FALSE;
4485 }
4486
4487 if (! ::PeekNamedPipe(han, NULL, 0, NULL, (LPDWORD)pbytes, NULL)) {
4488 // PeekNamedPipe fails when at EOF. In that case we
4489 // simply make *pbytes = 0 which is consistent with the
4490 // behavior we get on Solaris when an fd is at EOF.
4491 // The only alternative is to raise an Exception,
4492 // which isn't really warranted.
4493 //
4494 if (::GetLastError() != ERROR_BROKEN_PIPE) {
4495 return FALSE;
4496 }
4497 *pbytes = 0;
4498 }
4499 return TRUE;
4500 }
4501
4502 #define MAX_INPUT_EVENTS 2000
4503
4504 // This code is a copy of JDK's stdinAvailable
4505 // from src/windows/hpi/src/sys_api_md.c
4506
4507 static int stdinAvailable(int fd, long *pbytes) {
4508 HANDLE han;
4509 DWORD numEventsRead = 0; // Number of events read from buffer
4510 DWORD numEvents = 0; // Number of events in buffer
4511 DWORD i = 0; // Loop index
4512 DWORD curLength = 0; // Position marker
4513 DWORD actualLength = 0; // Number of bytes readable
4514 BOOL error = FALSE; // Error holder
4515 INPUT_RECORD *lpBuffer; // Pointer to records of input events
4516
4517 if ((han = ::GetStdHandle(STD_INPUT_HANDLE)) == INVALID_HANDLE_VALUE) {
4518 return FALSE;
4519 }
4520
4521 // Construct an array of input records in the console buffer
4522 error = ::GetNumberOfConsoleInputEvents(han, &numEvents);
4523 if (error == 0) {
4524 return nonSeekAvailable(fd, pbytes);
4525 }
4526
4527 // lpBuffer must fit into 64K or else PeekConsoleInput fails
4528 if (numEvents > MAX_INPUT_EVENTS) {
4529 numEvents = MAX_INPUT_EVENTS;
4530 }
4531
4532 lpBuffer = (INPUT_RECORD *)os::malloc(numEvents * sizeof(INPUT_RECORD), mtInternal);
4533 if (lpBuffer == NULL) {
4534 return FALSE;
4535 }
4536
4537 error = ::PeekConsoleInput(han, lpBuffer, numEvents, &numEventsRead);
4538 if (error == 0) {
4539 os::free(lpBuffer);
4540 return FALSE;
4541 }
4542
4543 // Examine input records for the number of bytes available
4544 for (i=0; i<numEvents; i++) {
4545 if (lpBuffer[i].EventType == KEY_EVENT) {
4546
4547 KEY_EVENT_RECORD *keyRecord = (KEY_EVENT_RECORD *)
4548 &(lpBuffer[i].Event);
4549 if (keyRecord->bKeyDown == TRUE) {
4550 CHAR *keyPressed = (CHAR *) &(keyRecord->uChar);
4551 curLength++;
4552 if (*keyPressed == '\r') {
4553 actualLength = curLength;
4554 }
4555 }
4556 }
4557 }
4558
4559 if (lpBuffer != NULL) {
4560 os::free(lpBuffer);
4561 }
4562
4563 *pbytes = (long) actualLength;
4564 return TRUE;
4565 }
4566
4567 // Map a block of memory.
4568 char* os::pd_map_memory(int fd, const char* file_name, size_t file_offset,
4569 char *addr, size_t bytes, bool read_only,
4570 bool allow_exec) {
4571 HANDLE hFile;
4572 char* base;
4573
4574 hFile = CreateFile(file_name, GENERIC_READ, FILE_SHARE_READ, NULL,
4575 OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
4576 if (hFile == NULL) {
4577 log_info(os)("CreateFile() failed: GetLastError->%ld.", GetLastError());
4578 return NULL;
4579 }
4580
4581 if (allow_exec) {
4582 // CreateFileMapping/MapViewOfFileEx can't map executable memory
4583 // unless it comes from a PE image (which the shared archive is not.)
4584 // Even VirtualProtect refuses to give execute access to mapped memory
4585 // that was not previously executable.
4586 //
4587 // Instead, stick the executable region in anonymous memory. Yuck.
4588 // Penalty is that ~4 pages will not be shareable - in the future
4589 // we might consider DLLizing the shared archive with a proper PE
4590 // header so that mapping executable + sharing is possible.
4591
4592 base = (char*) VirtualAlloc(addr, bytes, MEM_COMMIT | MEM_RESERVE,
4593 PAGE_READWRITE);
4594 if (base == NULL) {
4595 log_info(os)("VirtualAlloc() failed: GetLastError->%ld.", GetLastError());
4596 CloseHandle(hFile);
4597 return NULL;
4598 }
4599
4600 DWORD bytes_read;
4601 OVERLAPPED overlapped;
4602 overlapped.Offset = (DWORD)file_offset;
4603 overlapped.OffsetHigh = 0;
4604 overlapped.hEvent = NULL;
4605 // ReadFile guarantees that if the return value is true, the requested
4606 // number of bytes were read before returning.
4607 bool res = ReadFile(hFile, base, (DWORD)bytes, &bytes_read, &overlapped) != 0;
4608 if (!res) {
4609 log_info(os)("ReadFile() failed: GetLastError->%ld.", GetLastError());
4610 release_memory(base, bytes);
4611 CloseHandle(hFile);
4612 return NULL;
4613 }
4614 } else {
4615 HANDLE hMap = CreateFileMapping(hFile, NULL, PAGE_WRITECOPY, 0, 0,
4616 NULL /* file_name */);
4617 if (hMap == NULL) {
4618 log_info(os)("CreateFileMapping() failed: GetLastError->%ld.", GetLastError());
4619 CloseHandle(hFile);
4620 return NULL;
4621 }
4622
4623 DWORD access = read_only ? FILE_MAP_READ : FILE_MAP_COPY;
4624 base = (char*)MapViewOfFileEx(hMap, access, 0, (DWORD)file_offset,
4625 (DWORD)bytes, addr);
4626 if (base == NULL) {
4627 log_info(os)("MapViewOfFileEx() failed: GetLastError->%ld.", GetLastError());
4628 CloseHandle(hMap);
4629 CloseHandle(hFile);
4630 return NULL;
4631 }
4632
4633 if (CloseHandle(hMap) == 0) {
4634 log_info(os)("CloseHandle(hMap) failed: GetLastError->%ld.", GetLastError());
4635 CloseHandle(hFile);
4636 return base;
4637 }
4638 }
4639
4640 if (allow_exec) {
4641 DWORD old_protect;
4642 DWORD exec_access = read_only ? PAGE_EXECUTE_READ : PAGE_EXECUTE_READWRITE;
4643 bool res = VirtualProtect(base, bytes, exec_access, &old_protect) != 0;
4644
4645 if (!res) {
4646 log_info(os)("VirtualProtect() failed: GetLastError->%ld.", GetLastError());
4647 // Don't consider this a hard error, on IA32 even if the
4648 // VirtualProtect fails, we should still be able to execute
4649 CloseHandle(hFile);
4650 return base;
4651 }
4652 }
4653
4654 if (CloseHandle(hFile) == 0) {
4655 log_info(os)("CloseHandle(hFile) failed: GetLastError->%ld.", GetLastError());
4656 return base;
4657 }
4658
4659 return base;
4660 }
4661
4662
4663 // Remap a block of memory.
4664 char* os::pd_remap_memory(int fd, const char* file_name, size_t file_offset,
4665 char *addr, size_t bytes, bool read_only,
4666 bool allow_exec) {
4667 // This OS does not allow existing memory maps to be remapped so we
4668 // have to unmap the memory before we remap it.
4669 if (!os::unmap_memory(addr, bytes)) {
4670 return NULL;
4671 }
4672
4673 // There is a very small theoretical window between the unmap_memory()
4674 // call above and the map_memory() call below where a thread in native
4675 // code may be able to access an address that is no longer mapped.
4676
4677 return os::map_memory(fd, file_name, file_offset, addr, bytes,
4678 read_only, allow_exec);
4679 }
4680
4681
4682 // Unmap a block of memory.
4683 // Returns true=success, otherwise false.
4684
4685 bool os::pd_unmap_memory(char* addr, size_t bytes) {
4686 MEMORY_BASIC_INFORMATION mem_info;
4687 if (VirtualQuery(addr, &mem_info, sizeof(mem_info)) == 0) {
4688 log_info(os)("VirtualQuery() failed: GetLastError->%ld.", GetLastError());
4689 return false;
4690 }
4691
4692 // Executable memory was not mapped using CreateFileMapping/MapViewOfFileEx.
4693 // Instead, executable region was allocated using VirtualAlloc(). See
4694 // pd_map_memory() above.
4695 //
4696 // The following flags should match the 'exec_access' flages used for
4697 // VirtualProtect() in pd_map_memory().
4698 if (mem_info.Protect == PAGE_EXECUTE_READ ||
4699 mem_info.Protect == PAGE_EXECUTE_READWRITE) {
4700 return pd_release_memory(addr, bytes);
4701 }
4702
4703 BOOL result = UnmapViewOfFile(addr);
4704 if (result == 0) {
4705 log_info(os)("UnmapViewOfFile() failed: GetLastError->%ld.", GetLastError());
4706 return false;
4707 }
4708 return true;
4709 }
4710
4711 void os::pause() {
4712 char filename[MAX_PATH];
4713 if (PauseAtStartupFile && PauseAtStartupFile[0]) {
4714 jio_snprintf(filename, MAX_PATH, PauseAtStartupFile);
4715 } else {
4716 jio_snprintf(filename, MAX_PATH, "./vm.paused.%d", current_process_id());
4717 }
4718
4719 int fd = ::open(filename, O_WRONLY | O_CREAT | O_TRUNC, 0666);
4720 if (fd != -1) {
4721 struct stat buf;
4722 ::close(fd);
4723 while (::stat(filename, &buf) == 0) {
4724 Sleep(100);
4725 }
4726 } else {
4727 jio_fprintf(stderr,
4728 "Could not open pause file '%s', continuing immediately.\n", filename);
4729 }
4730 }
4731
4732 Thread* os::ThreadCrashProtection::_protected_thread = NULL;
4733 os::ThreadCrashProtection* os::ThreadCrashProtection::_crash_protection = NULL;
4734 volatile intptr_t os::ThreadCrashProtection::_crash_mux = 0;
4735
4736 os::ThreadCrashProtection::ThreadCrashProtection() {
4737 }
4738
4739 // See the caveats for this class in os_windows.hpp
4740 // Protects the callback call so that raised OS EXCEPTIONS causes a jump back
4741 // into this method and returns false. If no OS EXCEPTION was raised, returns
4742 // true.
4743 // The callback is supposed to provide the method that should be protected.
4744 //
4745 bool os::ThreadCrashProtection::call(os::CrashProtectionCallback& cb) {
4746
4747 Thread::muxAcquire(&_crash_mux, "CrashProtection");
4748
4749 _protected_thread = Thread::current_or_null();
4750 assert(_protected_thread != NULL, "Cannot crash protect a NULL thread");
4751
4752 bool success = true;
4753 __try {
4754 _crash_protection = this;
4755 cb.call();
4756 } __except(EXCEPTION_EXECUTE_HANDLER) {
4757 // only for protection, nothing to do
4758 success = false;
4759 }
4760 _crash_protection = NULL;
4761 _protected_thread = NULL;
4762 Thread::muxRelease(&_crash_mux);
4763 return success;
4764 }
4765
4766 // An Event wraps a win32 "CreateEvent" kernel handle.
4767 //
4768 // We have a number of choices regarding "CreateEvent" win32 handle leakage:
4769 //
4770 // 1: When a thread dies return the Event to the EventFreeList, clear the ParkHandle
4771 // field, and call CloseHandle() on the win32 event handle. Unpark() would
4772 // need to be modified to tolerate finding a NULL (invalid) win32 event handle.
4773 // In addition, an unpark() operation might fetch the handle field, but the
4774 // event could recycle between the fetch and the SetEvent() operation.
4775 // SetEvent() would either fail because the handle was invalid, or inadvertently work,
4776 // as the win32 handle value had been recycled. In an ideal world calling SetEvent()
4777 // on an stale but recycled handle would be harmless, but in practice this might
4778 // confuse other non-Sun code, so it's not a viable approach.
4779 //
4780 // 2: Once a win32 event handle is associated with an Event, it remains associated
4781 // with the Event. The event handle is never closed. This could be construed
4782 // as handle leakage, but only up to the maximum # of threads that have been extant
4783 // at any one time. This shouldn't be an issue, as windows platforms typically
4784 // permit a process to have hundreds of thousands of open handles.
4785 //
4786 // 3: Same as (1), but periodically, at stop-the-world time, rundown the EventFreeList
4787 // and release unused handles.
4788 //
4789 // 4: Add a CRITICAL_SECTION to the Event to protect LD+SetEvent from LD;ST(null);CloseHandle.
4790 // It's not clear, however, that we wouldn't be trading one type of leak for another.
4791 //
4792 // 5. Use an RCU-like mechanism (Read-Copy Update).
4793 // Or perhaps something similar to Maged Michael's "Hazard pointers".
4794 //
4795 // We use (2).
4796 //
4797 // TODO-FIXME:
4798 // 1. Reconcile Doug's JSR166 j.u.c park-unpark with the objectmonitor implementation.
4799 // 2. Consider wrapping the WaitForSingleObject(Ex) calls in SEH try/finally blocks
4800 // to recover from (or at least detect) the dreaded Windows 841176 bug.
4801 // 3. Collapse the interrupt_event, the JSR166 parker event, and the objectmonitor ParkEvent
4802 // into a single win32 CreateEvent() handle.
4803 //
4804 // Assumption:
4805 // Only one parker can exist on an event, which is why we allocate
4806 // them per-thread. Multiple unparkers can coexist.
4807 //
4808 // _Event transitions in park()
4809 // -1 => -1 : illegal
4810 // 1 => 0 : pass - return immediately
4811 // 0 => -1 : block; then set _Event to 0 before returning
4812 //
4813 // _Event transitions in unpark()
4814 // 0 => 1 : just return
4815 // 1 => 1 : just return
4816 // -1 => either 0 or 1; must signal target thread
4817 // That is, we can safely transition _Event from -1 to either
4818 // 0 or 1.
4819 //
4820 // _Event serves as a restricted-range semaphore.
4821 // -1 : thread is blocked, i.e. there is a waiter
4822 // 0 : neutral: thread is running or ready,
4823 // could have been signaled after a wait started
4824 // 1 : signaled - thread is running or ready
4825 //
4826 // Another possible encoding of _Event would be with
4827 // explicit "PARKED" == 01b and "SIGNALED" == 10b bits.
4828 //
4829
4830 int os::PlatformEvent::park(jlong Millis) {
4831 // Transitions for _Event:
4832 // -1 => -1 : illegal
4833 // 1 => 0 : pass - return immediately
4834 // 0 => -1 : block; then set _Event to 0 before returning
4835
4836 guarantee(_ParkHandle != NULL , "Invariant");
4837 guarantee(Millis > 0 , "Invariant");
4838
4839 // CONSIDER: defer assigning a CreateEvent() handle to the Event until
4840 // the initial park() operation.
4841 // Consider: use atomic decrement instead of CAS-loop
4842
4843 int v;
4844 for (;;) {
4845 v = _Event;
4846 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4847 }
4848 guarantee((v == 0) || (v == 1), "invariant");
4849 if (v != 0) return OS_OK;
4850
4851 // Do this the hard way by blocking ...
4852 // TODO: consider a brief spin here, gated on the success of recent
4853 // spin attempts by this thread.
4854 //
4855 // We decompose long timeouts into series of shorter timed waits.
4856 // Evidently large timo values passed in WaitForSingleObject() are problematic on some
4857 // versions of Windows. See EventWait() for details. This may be superstition. Or not.
4858 // We trust the WAIT_TIMEOUT indication and don't track the elapsed wait time
4859 // with os::javaTimeNanos(). Furthermore, we assume that spurious returns from
4860 // ::WaitForSingleObject() caused by latent ::setEvent() operations will tend
4861 // to happen early in the wait interval. Specifically, after a spurious wakeup (rv ==
4862 // WAIT_OBJECT_0 but _Event is still < 0) we don't bother to recompute Millis to compensate
4863 // for the already waited time. This policy does not admit any new outcomes.
4864 // In the future, however, we might want to track the accumulated wait time and
4865 // adjust Millis accordingly if we encounter a spurious wakeup.
4866
4867 const int MAXTIMEOUT = 0x10000000;
4868 DWORD rv = WAIT_TIMEOUT;
4869 while (_Event < 0 && Millis > 0) {
4870 DWORD prd = Millis; // set prd = MAX (Millis, MAXTIMEOUT)
4871 if (Millis > MAXTIMEOUT) {
4872 prd = MAXTIMEOUT;
4873 }
4874 rv = ::WaitForSingleObject(_ParkHandle, prd);
4875 assert(rv == WAIT_OBJECT_0 || rv == WAIT_TIMEOUT, "WaitForSingleObject failed");
4876 if (rv == WAIT_TIMEOUT) {
4877 Millis -= prd;
4878 }
4879 }
4880 v = _Event;
4881 _Event = 0;
4882 // see comment at end of os::PlatformEvent::park() below:
4883 OrderAccess::fence();
4884 // If we encounter a nearly simultanous timeout expiry and unpark()
4885 // we return OS_OK indicating we awoke via unpark().
4886 // Implementor's license -- returning OS_TIMEOUT would be equally valid, however.
4887 return (v >= 0) ? OS_OK : OS_TIMEOUT;
4888 }
4889
4890 void os::PlatformEvent::park() {
4891 // Transitions for _Event:
4892 // -1 => -1 : illegal
4893 // 1 => 0 : pass - return immediately
4894 // 0 => -1 : block; then set _Event to 0 before returning
4895
4896 guarantee(_ParkHandle != NULL, "Invariant");
4897 // Invariant: Only the thread associated with the Event/PlatformEvent
4898 // may call park().
4899 // Consider: use atomic decrement instead of CAS-loop
4900 int v;
4901 for (;;) {
4902 v = _Event;
4903 if (Atomic::cmpxchg(v-1, &_Event, v) == v) break;
4904 }
4905 guarantee((v == 0) || (v == 1), "invariant");
4906 if (v != 0) return;
4907
4908 // Do this the hard way by blocking ...
4909 // TODO: consider a brief spin here, gated on the success of recent
4910 // spin attempts by this thread.
4911 while (_Event < 0) {
4912 DWORD rv = ::WaitForSingleObject(_ParkHandle, INFINITE);
4913 assert(rv == WAIT_OBJECT_0, "WaitForSingleObject failed");
4914 }
4915
4916 // Usually we'll find _Event == 0 at this point, but as
4917 // an optional optimization we clear it, just in case can
4918 // multiple unpark() operations drove _Event up to 1.
4919 _Event = 0;
4920 OrderAccess::fence();
4921 guarantee(_Event >= 0, "invariant");
4922 }
4923
4924 void os::PlatformEvent::unpark() {
4925 guarantee(_ParkHandle != NULL, "Invariant");
4926
4927 // Transitions for _Event:
4928 // 0 => 1 : just return
4929 // 1 => 1 : just return
4930 // -1 => either 0 or 1; must signal target thread
4931 // That is, we can safely transition _Event from -1 to either
4932 // 0 or 1.
4933 // See also: "Semaphores in Plan 9" by Mullender & Cox
4934 //
4935 // Note: Forcing a transition from "-1" to "1" on an unpark() means
4936 // that it will take two back-to-back park() calls for the owning
4937 // thread to block. This has the benefit of forcing a spurious return
4938 // from the first park() call after an unpark() call which will help
4939 // shake out uses of park() and unpark() without condition variables.
4940
4941 if (Atomic::xchg(1, &_Event) >= 0) return;
4942
4943 ::SetEvent(_ParkHandle);
4944 }
4945
4946
4947 // JSR166
4948 // -------------------------------------------------------
4949
4950 // The Windows implementation of Park is very straightforward: Basic
4951 // operations on Win32 Events turn out to have the right semantics to
4952 // use them directly. We opportunistically resuse the event inherited
4953 // from Monitor.
4954
4955 void Parker::park(bool isAbsolute, jlong time) {
4956 guarantee(_ParkEvent != NULL, "invariant");
4957 // First, demultiplex/decode time arguments
4958 if (time < 0) { // don't wait
4959 return;
4960 } else if (time == 0 && !isAbsolute) {
4961 time = INFINITE;
4962 } else if (isAbsolute) {
4963 time -= os::javaTimeMillis(); // convert to relative time
4964 if (time <= 0) { // already elapsed
4965 return;
4966 }
4967 } else { // relative
4968 time /= 1000000; // Must coarsen from nanos to millis
4969 if (time == 0) { // Wait for the minimal time unit if zero
4970 time = 1;
4971 }
4972 }
4973
4974 JavaThread* thread = JavaThread::current();
4975
4976 // Don't wait if interrupted or already triggered
4977 if (Thread::is_interrupted(thread, false) ||
4978 WaitForSingleObject(_ParkEvent, 0) == WAIT_OBJECT_0) {
4979 ResetEvent(_ParkEvent);
4980 return;
4981 } else {
4982 ThreadBlockInVM tbivm(thread);
4983 OSThreadWaitState osts(thread->osthread(), false /* not Object.wait() */);
4984 thread->set_suspend_equivalent();
4985
4986 WaitForSingleObject(_ParkEvent, time);
4987 ResetEvent(_ParkEvent);
4988
4989 // If externally suspended while waiting, re-suspend
4990 if (thread->handle_special_suspend_equivalent_condition()) {
4991 thread->java_suspend_self();
4992 }
4993 }
4994 }
4995
4996 void Parker::unpark() {
4997 guarantee(_ParkEvent != NULL, "invariant");
4998 SetEvent(_ParkEvent);
4999 }
5000
5001 // Run the specified command in a separate process. Return its exit value,
5002 // or -1 on failure (e.g. can't create a new process).
5003 int os::fork_and_exec(char* cmd) {
5004 STARTUPINFO si;
5005 PROCESS_INFORMATION pi;
5006 DWORD exit_code;
5007
5008 char * cmd_string;
5009 char * cmd_prefix = "cmd /C ";
5010 size_t len = strlen(cmd) + strlen(cmd_prefix) + 1;
5011 cmd_string = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtInternal);
5012 if (cmd_string == NULL) {
5013 return -1;
5014 }
5015 cmd_string[0] = '\0';
5016 strcat(cmd_string, cmd_prefix);
5017 strcat(cmd_string, cmd);
5018
5019 // now replace all '\n' with '&'
5020 char * substring = cmd_string;
5021 while ((substring = strchr(substring, '\n')) != NULL) {
5022 substring[0] = '&';
5023 substring++;
5024 }
5025 memset(&si, 0, sizeof(si));
5026 si.cb = sizeof(si);
5027 memset(&pi, 0, sizeof(pi));
5028 BOOL rslt = CreateProcess(NULL, // executable name - use command line
5029 cmd_string, // command line
5030 NULL, // process security attribute
5031 NULL, // thread security attribute
5032 TRUE, // inherits system handles
5033 0, // no creation flags
5034 NULL, // use parent's environment block
5035 NULL, // use parent's starting directory
5036 &si, // (in) startup information
5037 &pi); // (out) process information
5038
5039 if (rslt) {
5040 // Wait until child process exits.
5041 WaitForSingleObject(pi.hProcess, INFINITE);
5042
5043 GetExitCodeProcess(pi.hProcess, &exit_code);
5044
5045 // Close process and thread handles.
5046 CloseHandle(pi.hProcess);
5047 CloseHandle(pi.hThread);
5048 } else {
5049 exit_code = -1;
5050 }
5051
5052 FREE_C_HEAP_ARRAY(char, cmd_string);
5053 return (int)exit_code;
5054 }
5055
5056 bool os::find(address addr, outputStream* st) {
5057 int offset = -1;
5058 bool result = false;
5059 char buf[256];
5060 if (os::dll_address_to_library_name(addr, buf, sizeof(buf), &offset)) {
5061 st->print(PTR_FORMAT " ", addr);
5062 if (strlen(buf) < sizeof(buf) - 1) {
5063 char* p = strrchr(buf, '\\');
5064 if (p) {
5065 st->print("%s", p + 1);
5066 } else {
5067 st->print("%s", buf);
5068 }
5069 } else {
5070 // The library name is probably truncated. Let's omit the library name.
5071 // See also JDK-8147512.
5072 }
5073 if (os::dll_address_to_function_name(addr, buf, sizeof(buf), &offset)) {
5074 st->print("::%s + 0x%x", buf, offset);
5075 }
5076 st->cr();
5077 result = true;
5078 }
5079 return result;
5080 }
5081
5082 LONG WINAPI os::win32::serialize_fault_filter(struct _EXCEPTION_POINTERS* e) {
5083 DWORD exception_code = e->ExceptionRecord->ExceptionCode;
5084
5085 if (exception_code == EXCEPTION_ACCESS_VIOLATION) {
5086 JavaThread* thread = JavaThread::current();
5087 PEXCEPTION_RECORD exceptionRecord = e->ExceptionRecord;
5088 address addr = (address) exceptionRecord->ExceptionInformation[1];
5089
5090 if (os::is_memory_serialize_page(thread, addr)) {
5091 return EXCEPTION_CONTINUE_EXECUTION;
5092 }
5093 }
5094
5095 return EXCEPTION_CONTINUE_SEARCH;
5096 }
5097
5098 // We don't build a headless jre for Windows
5099 bool os::is_headless_jre() { return false; }
5100
5101 static jint initSock() {
5102 WSADATA wsadata;
5103
5104 if (WSAStartup(MAKEWORD(2,2), &wsadata) != 0) {
5105 jio_fprintf(stderr, "Could not initialize Winsock (error: %d)\n",
5106 ::GetLastError());
5107 return JNI_ERR;
5108 }
5109 return JNI_OK;
5110 }
5111
5112 struct hostent* os::get_host_by_name(char* name) {
5113 return (struct hostent*)gethostbyname(name);
5114 }
5115
5116 int os::socket_close(int fd) {
5117 return ::closesocket(fd);
5118 }
5119
5120 int os::socket(int domain, int type, int protocol) {
5121 return ::socket(domain, type, protocol);
5122 }
5123
5124 int os::connect(int fd, struct sockaddr* him, socklen_t len) {
5125 return ::connect(fd, him, len);
5126 }
5127
5128 int os::recv(int fd, char* buf, size_t nBytes, uint flags) {
5129 return ::recv(fd, buf, (int)nBytes, flags);
5130 }
5131
5132 int os::send(int fd, char* buf, size_t nBytes, uint flags) {
5133 return ::send(fd, buf, (int)nBytes, flags);
5134 }
5135
5136 int os::raw_send(int fd, char* buf, size_t nBytes, uint flags) {
5137 return ::send(fd, buf, (int)nBytes, flags);
5138 }
5139
5140 // WINDOWS CONTEXT Flags for THREAD_SAMPLING
5141 #if defined(IA32)
5142 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT | CONTEXT_EXTENDED_REGISTERS)
5143 #elif defined (AMD64)
5144 #define sampling_context_flags (CONTEXT_FULL | CONTEXT_FLOATING_POINT)
5145 #endif
5146
5147 // returns true if thread could be suspended,
5148 // false otherwise
5149 static bool do_suspend(HANDLE* h) {
5150 if (h != NULL) {
5151 if (SuspendThread(*h) != ~0) {
5152 return true;
5153 }
5154 }
5155 return false;
5156 }
5157
5158 // resume the thread
5159 // calling resume on an active thread is a no-op
5160 static void do_resume(HANDLE* h) {
5161 if (h != NULL) {
5162 ResumeThread(*h);
5163 }
5164 }
5165
5166 // retrieve a suspend/resume context capable handle
5167 // from the tid. Caller validates handle return value.
5168 void get_thread_handle_for_extended_context(HANDLE* h,
5169 OSThread::thread_id_t tid) {
5170 if (h != NULL) {
5171 *h = OpenThread(THREAD_SUSPEND_RESUME | THREAD_GET_CONTEXT | THREAD_QUERY_INFORMATION, FALSE, tid);
5172 }
5173 }
5174
5175 // Thread sampling implementation
5176 //
5177 void os::SuspendedThreadTask::internal_do_task() {
5178 CONTEXT ctxt;
5179 HANDLE h = NULL;
5180
5181 // get context capable handle for thread
5182 get_thread_handle_for_extended_context(&h, _thread->osthread()->thread_id());
5183
5184 // sanity
5185 if (h == NULL || h == INVALID_HANDLE_VALUE) {
5186 return;
5187 }
5188
5189 // suspend the thread
5190 if (do_suspend(&h)) {
5191 ctxt.ContextFlags = sampling_context_flags;
5192 // get thread context
5193 GetThreadContext(h, &ctxt);
5194 SuspendedThreadTaskContext context(_thread, &ctxt);
5195 // pass context to Thread Sampling impl
5196 do_task(context);
5197 // resume thread
5198 do_resume(&h);
5199 }
5200
5201 // close handle
5202 CloseHandle(h);
5203 }
5204
5205 bool os::start_debugging(char *buf, int buflen) {
5206 int len = (int)strlen(buf);
5207 char *p = &buf[len];
5208
5209 jio_snprintf(p, buflen-len,
5210 "\n\n"
5211 "Do you want to debug the problem?\n\n"
5212 "To debug, attach Visual Studio to process %d; then switch to thread 0x%x\n"
5213 "Select 'Yes' to launch Visual Studio automatically (PATH must include msdev)\n"
5214 "Otherwise, select 'No' to abort...",
5215 os::current_process_id(), os::current_thread_id());
5216
5217 bool yes = os::message_box("Unexpected Error", buf);
5218
5219 if (yes) {
5220 // os::breakpoint() calls DebugBreak(), which causes a breakpoint
5221 // exception. If VM is running inside a debugger, the debugger will
5222 // catch the exception. Otherwise, the breakpoint exception will reach
5223 // the default windows exception handler, which can spawn a debugger and
5224 // automatically attach to the dying VM.
5225 os::breakpoint();
5226 yes = false;
5227 }
5228 return yes;
5229 }
5230
5231 void* os::get_default_process_handle() {
5232 return (void*)GetModuleHandle(NULL);
5233 }
5234
5235 // Builds a platform dependent Agent_OnLoad_<lib_name> function name
5236 // which is used to find statically linked in agents.
5237 // Additionally for windows, takes into account __stdcall names.
5238 // Parameters:
5239 // sym_name: Symbol in library we are looking for
5240 // lib_name: Name of library to look in, NULL for shared libs.
5241 // is_absolute_path == true if lib_name is absolute path to agent
5242 // such as "C:/a/b/L.dll"
5243 // == false if only the base name of the library is passed in
5244 // such as "L"
5245 char* os::build_agent_function_name(const char *sym_name, const char *lib_name,
5246 bool is_absolute_path) {
5247 char *agent_entry_name;
5248 size_t len;
5249 size_t name_len;
5250 size_t prefix_len = strlen(JNI_LIB_PREFIX);
5251 size_t suffix_len = strlen(JNI_LIB_SUFFIX);
5252 const char *start;
5253
5254 if (lib_name != NULL) {
5255 len = name_len = strlen(lib_name);
5256 if (is_absolute_path) {
5257 // Need to strip path, prefix and suffix
5258 if ((start = strrchr(lib_name, *os::file_separator())) != NULL) {
5259 lib_name = ++start;
5260 } else {
5261 // Need to check for drive prefix
5262 if ((start = strchr(lib_name, ':')) != NULL) {
5263 lib_name = ++start;
5264 }
5265 }
5266 if (len <= (prefix_len + suffix_len)) {
5267 return NULL;
5268 }
5269 lib_name += prefix_len;
5270 name_len = strlen(lib_name) - suffix_len;
5271 }
5272 }
5273 len = (lib_name != NULL ? name_len : 0) + strlen(sym_name) + 2;
5274 agent_entry_name = NEW_C_HEAP_ARRAY_RETURN_NULL(char, len, mtThread);
5275 if (agent_entry_name == NULL) {
5276 return NULL;
5277 }
5278 if (lib_name != NULL) {
5279 const char *p = strrchr(sym_name, '@');
5280 if (p != NULL && p != sym_name) {
5281 // sym_name == _Agent_OnLoad@XX
5282 strncpy(agent_entry_name, sym_name, (p - sym_name));
5283 agent_entry_name[(p-sym_name)] = '\0';
5284 // agent_entry_name == _Agent_OnLoad
5285 strcat(agent_entry_name, "_");
5286 strncat(agent_entry_name, lib_name, name_len);
5287 strcat(agent_entry_name, p);
5288 // agent_entry_name == _Agent_OnLoad_lib_name@XX
5289 } else {
5290 strcpy(agent_entry_name, sym_name);
5291 strcat(agent_entry_name, "_");
5292 strncat(agent_entry_name, lib_name, name_len);
5293 }
5294 } else {
5295 strcpy(agent_entry_name, sym_name);
5296 }
5297 return agent_entry_name;
5298 }
5299
5300 #ifndef PRODUCT
5301
5302 // test the code path in reserve_memory_special() that tries to allocate memory in a single
5303 // contiguous memory block at a particular address.
5304 // The test first tries to find a good approximate address to allocate at by using the same
5305 // method to allocate some memory at any address. The test then tries to allocate memory in
5306 // the vicinity (not directly after it to avoid possible by-chance use of that location)
5307 // This is of course only some dodgy assumption, there is no guarantee that the vicinity of
5308 // the previously allocated memory is available for allocation. The only actual failure
5309 // that is reported is when the test tries to allocate at a particular location but gets a
5310 // different valid one. A NULL return value at this point is not considered an error but may
5311 // be legitimate.
5312 // If -XX:+VerboseInternalVMTests is enabled, print some explanatory messages.
5313 void TestReserveMemorySpecial_test() {
5314 if (!UseLargePages) {
5315 if (VerboseInternalVMTests) {
5316 tty->print("Skipping test because large pages are disabled");
5317 }
5318 return;
5319 }
5320 // save current value of globals
5321 bool old_use_large_pages_individual_allocation = UseLargePagesIndividualAllocation;
5322 bool old_use_numa_interleaving = UseNUMAInterleaving;
5323
5324 // set globals to make sure we hit the correct code path
5325 UseLargePagesIndividualAllocation = UseNUMAInterleaving = false;
5326
5327 // do an allocation at an address selected by the OS to get a good one.
5328 const size_t large_allocation_size = os::large_page_size() * 4;
5329 char* result = os::reserve_memory_special(large_allocation_size, os::large_page_size(), NULL, false);
5330 if (result == NULL) {
5331 if (VerboseInternalVMTests) {
5332 tty->print("Failed to allocate control block with size " SIZE_FORMAT ". Skipping remainder of test.",
5333 large_allocation_size);
5334 }
5335 } else {
5336 os::release_memory_special(result, large_allocation_size);
5337
5338 // allocate another page within the recently allocated memory area which seems to be a good location. At least
5339 // we managed to get it once.
5340 const size_t expected_allocation_size = os::large_page_size();
5341 char* expected_location = result + os::large_page_size();
5342 char* actual_location = os::reserve_memory_special(expected_allocation_size, os::large_page_size(), expected_location, false);
5343 if (actual_location == NULL) {
5344 if (VerboseInternalVMTests) {
5345 tty->print("Failed to allocate any memory at " PTR_FORMAT " size " SIZE_FORMAT ". Skipping remainder of test.",
5346 expected_location, large_allocation_size);
5347 }
5348 } else {
5349 // release memory
5350 os::release_memory_special(actual_location, expected_allocation_size);
5351 // only now check, after releasing any memory to avoid any leaks.
5352 assert(actual_location == expected_location,
5353 "Failed to allocate memory at requested location " PTR_FORMAT " of size " SIZE_FORMAT ", is " PTR_FORMAT " instead",
5354 expected_location, expected_allocation_size, actual_location);
5355 }
5356 }
5357
5358 // restore globals
5359 UseLargePagesIndividualAllocation = old_use_large_pages_individual_allocation;
5360 UseNUMAInterleaving = old_use_numa_interleaving;
5361 }
5362 #endif // PRODUCT
5363
5364 /*
5365 All the defined signal names for Windows.
5366
5367 NOTE that not all of these names are accepted by FindSignal!
5368
5369 For various reasons some of these may be rejected at runtime.
5370
5371 Here are the names currently accepted by a user of sun.misc.Signal with
5372 1.4.1 (ignoring potential interaction with use of chaining, etc):
5373
5374 (LIST TBD)
5375
5376 */
5377 int os::get_signal_number(const char* name) {
5378 static const struct {
5379 char* name;
5380 int number;
5381 } siglabels [] =
5382 // derived from version 6.0 VC98/include/signal.h
5383 {"ABRT", SIGABRT, // abnormal termination triggered by abort cl
5384 "FPE", SIGFPE, // floating point exception
5385 "SEGV", SIGSEGV, // segment violation
5386 "INT", SIGINT, // interrupt
5387 "TERM", SIGTERM, // software term signal from kill
5388 "BREAK", SIGBREAK, // Ctrl-Break sequence
5389 "ILL", SIGILL}; // illegal instruction
5390 for (unsigned i = 0; i < ARRAY_SIZE(siglabels); ++i) {
5391 if (strcmp(name, siglabels[i].name) == 0) {
5392 return siglabels[i].number;
5393 }
5394 }
5395 return -1;
5396 }
5397
5398 // Fast current thread access
5399
5400 int os::win32::_thread_ptr_offset = 0;
5401
5402 static void call_wrapper_dummy() {}
5403
5404 // We need to call the os_exception_wrapper once so that it sets
5405 // up the offset from FS of the thread pointer.
5406 void os::win32::initialize_thread_ptr_offset() {
5407 os::os_exception_wrapper((java_call_t)call_wrapper_dummy,
5408 NULL, NULL, NULL, NULL);
5409 }